• Option C is correct.
• Salinization of soil is an excessive accumulation of water-soluble salts. Typically, it is table salt NaCl. The list is far more extensive and includes various compounds of sodium, potassium, calcium, magnesium, sulfates, chlorides, carbohydrates, and bicarbonates.
• There are several techniques to tackle salinization and improve agricultural productivity:
1.Increase drainage for better flushing (to remove salts from the ground surface).(Hence, option 1 is correct)
2.Plant salt-tolerant crops to manage economic risks and to ensure land cover.
3.Remove salt crystals from the surface mechanically.
4.Restore the balance via chemical amendments (e.g., gypsum or sulfuric acid).
5.Pre-treat seeds with NaCl to promote seed germination.(Hence, option 2 is correct)
6.Reduce evaporation with mulch or crop residue. (Hence, option 3 is incorrect)
7.Grow crops that can absorb moisture properly to avoid prolonged wetness of lands.
8.Apply fertilizers rationally, as an overuse of certain chemicals promote salinization.
9.Restrain from deep tillage/heavy machinery not to transfer soil salts to the root zone area, which induces salinization.(Hence, option 4 is incorrect)

• Option B is correct.
• Biological contaminants (bio-contaminants) are pollutants of biological origin. Major components in the air include microbes (bacteria, viruses, unicellular organisms), fungi, algae, mites, insect debris/animal epithelia, and their by-products . By controlling the relative humidity level in a home, the growth of some sources of biologicals can be minimized
• Blue-green algae blooms are harmful when they produce toxins that can make humans and animals sick.
• Basidiospores are reproductive spores generated by Basidiomycete fungus, including mushrooms, shelf fungi, rusts, and smuts. Basidiospores are allergen and can cause respiratory disease.
• Pesticides are not biological contaminants. They are considered to be chemical contaminants.

• Option B is correct.
• Forest fires can have immediate and long term effects on the quality of rivers, lakes, and streams. The most noticeable impact of wildfires is stormwater runoff. After the loss of vegetation, the ground’s soil becomes hydrophobic (Hence,statement 1 is incorrect) and prevents the absorption of water.
• This inability to absorb water promotes the transportation of debris and sediment into larger bodies of water, (Hence,statement 3 is correct) further polluting valuable and essential resources. Post-fire flash floods become a threat and allow the introduction of heavy metals from ash and soil to infiltrate waterways.
• Forest fires help in recycling of nutrients bound up in litter.This is the idea also behind slash and burn cultivation practiced in various part of India (Hence,statement 2 is correct.)

• Option C is correct.
• Jhalaras are typically rectangular-shaped stepwells that have tiered steps on three or four sides. These stepwells collect the subterranean seepage of an upstream reservoir or a lake. Jhalaras were built to ensure easy and regular supply of water for religious rites, royal ceremonies and community use in the state of Gujarat and Rajasthan.Hence, pair 1 is not correctly matched.
• The Eri (tank) system of Tamil Nadu is one of the oldest water management systems in India. Still widely used in the state, eris act as flood-control systems, prevent soil erosion and wastage of runoff during periods of heavy rainfall, and also recharge the groundwater.Hence, pair 2 is correctly matched.
• Kuhls are surface water channels found in the mountainous regions of Himachal Pradesh. The channels carry glacial waters from rivers and streams into the fields. The Kangra Valley system has an estimated 715 major kuhls and 2,500 minor kuhls that irrigate more than 30,000 hectares in the valley. Hence, pair 3 is correctly matched.
• The Zabo (meaning ‘impounding run-off’) system combines water conservation with forestry, agriculture and animal care. Practiced in Nagaland, Zabo is also known as the Ruza system. Rainwater that falls on forested hilltops is collected by channels that deposit the run-off water in pond-like structures created on the terraced hillsides. Hence, pair 4 is incorrectly matched.

• Option A is correct.
• Unnecessary idling of cars, trucks, and school buses pollutes the air, wastes fuel, and causes excess engine wear. Modern vehicles do not require “warming up” in the winter, so there is no need to turn on the engine until you are ready to drive. Hence, statement 1 is correct.
• Sub-optimal tyre pressure is one of the primary causes of uncontrolled carbon dioxide emissions, compromised fuel economy, and increased vehicle pollution. Hence, statement 2 is correct.
• A catalytic converter is a device used to reduce the emissions from an internal combustion engine (automobiles and vehicles). Enough oxygen is not available to oxidize the carbon fuel in these engines completely into carbon dioxide and water; thus toxic by-products are produced. Catalytic converters are used in exhaust systems to provide a site for the oxidation and reduction of toxic by-products (like nitrogen oxides, carbon monoxide, and hydrocarbons) of fuel into less hazardous substances, such as carbon dioxide, water vapor, and nitrogen gas. Hence, statement 3 is incorrect.
• Cars using leaded petrol have higher emissions of highly dangerous particulate pollutants due to lead content in fuel. Long-term exposure to low levels of lead can affect mental development in children. The higher the average blood lead concentration in a population, the lower is their average IQ. Hence, statement 4 is incorrect.

• Option C is correct.
• The objective of the act is protection and improvement of the environment and the prevention of hazards to human beings, other living creatures, plants and property.Hence, statement 1 is correct.
• A potential drawback of the Act could be its centralization. While such wide powers are provided to the Centre and no powers to the state governments, the former is liable to its arbitrariness and misuse.Hence, statement 3 is correct.
• Under Section 19 of Environment (Protection) Act 1986, no court shall take cognizance of any offence under this Act except on a complaint made by– (a) the Central Government or any authority or officer authorized in this behalf by that Government , or (b) any person who has given notice of not less than sixty days, in the manner prescribed, of the alleged offence and of his intention to make a complaint, to the Central Government or the authority or officer authorized as aforesaid. Hence, statement 2 is incorrect.

• Option B is correct.
• CHAPTER IVA provides protection to the animals held in captivity. This chapter lays down recognition of zoo,prohibition of teasing of animals in zoo and procedure for acquisition of zoo. Hence, statement 1 is correct.
• In context of the act,“animal” includes amphibians, birds, mammals and reptiles and their young, and also includes, in the cases of birds and reptiles, their eggs. Hence,statement 2 is incorrect.

• Salient Features of the Act
Prohibition of hunting: It prohibits the hunting of any wild animal specified in Schedules I, II, III and IV of the act.
Exception: A wild animal listed under these schedules can be hunted/ killed only after getting permission from the Chief Wildlife Warden (CWLW) of the state if:
1. It becomes dangerous to human life or to property (including standing crops on any land).
2. It is disabled or suffering from a disease that is beyond recovery. Hence, statement 3 is correct.

Prohibition of Cutting/Uprooting Specified Plants: It prohibits the uprooting, damage, collection, possession or selling of any specified plant from any forest land or any protected area.
Exception: The CWLW, however, may grant permission for uprooting or collecting a specific plant for the purpose of education, scientific research, preservation in a herbarium or if a person/institution is approved to do so by the central government.

Declaration and Protection of Wildlife Sanctuaries and National Parks: The Central Government can constitute any area as a Sanctuary, provided the area is of adequate ecological, faunal, floral, geomorphological, natural or zoological significance. The government can also declare an area (including an area within a sanctuary) as a National Park.

• Option A is correct.
National Board for Wildlife (NBWL): The central government of India constitutes the National Board for Wildlife (NBWL).
It serves as an apex body for the review of all wildlife-related matters and for the approval of projects in and around national parks and sanctuaries. Hence, statement 1 is correct.
The NBWL is chaired by the Prime Minister and is responsible for promotion of conservation and development of wildlife and forests. Hence, statement 2 is incorrect.
The Minister of Environment, Forest and Climate Change is the Vice-Chairperson of the board.
The board is ‘advisory’ in nature and can only advise the Government on policy making for conservation of wildlife. Hence, statement 3 is incorrect.
Standing Committee of NBWL: The NBWL constitutes a Standing Committee for the purpose of approving all the projects falling within protected wildlife areas or within 10 km of them.
The committee is chaired by the Minister of Environment, Forest and Climate Change.

• Option A is correct.
• Incineration and pyrolysis are thermal decomposition methods. The key difference between incineration and pyrolysis is that incineration is the combustion of organic matter in the presence of oxygen whereas pyrolysis is the combustion of organic matter in the absence of oxygen.Hence, statements 1 and 2 are incorrect.
• Pyrolysis also turns waste into energy by heating under controlled conditions, but involves thermal degradation in the complete absence of air. Pyrolysis typically occurs under pressure and at operating temperatures above 430ºC (800ºF).Pyrolysis produces char, pyrolysis oil, and syngas, all of which can be used as fuels.Hence, statement 3 is correct.

• Option A is correct.
• The by-products of coal gasification slag and fly ash are formed in the gasifier reaction vessel. Hence,statement 3 is incorrect.
• Fly Ash has following economic value:
1.Cement can be replaced by fly ash upto 35%, thus reducing the cost of construction, making roads, etc.
2.Fly ash bricks are light in weight and offer high strength and durability.
3.Fly ash is a better fill material for road embankments and in concrete roads.
Hence,statement 2 is incorrect.
• Fly ash particles are oxide rich and consist of silica, alumina, oxides of iron, calcium, and magnesium and toxic heavy metals like lead, arsenic, cobalt, and copper. Hence,statement 1 is correct.