None of the above is incorrect.
A bioreactor may also refer to a device or system meant to grow cells or tissues in the context of cell culture.
These devices are being developed for use in tissue engineering or biochemical engineering. It can be used to treat sewage and wastewater.
A photobioreactor (PBR) is a bioreactor which incorporates some type of light source (that may be natural sunlight or artificial illumination). Photobioreactors are used to grow small phototrophic organisms such as cyanobacteria, algae, or moss plants.

1, 2 and 3 are correct.
The largest reservoir of Earth’s oxygen is within the silicate and oxide minerals of the crust and mantle (99.5%).
Only a small portion has been released as free oxygen to the biosphere (0.01%) and atmosphere (0.36%). The main source of atmospheric free oxygen is photosynthesis.
The processes that lead to loss of oxygen are:
• Aerobic respiration (largest – more than 75%)
• Microbial oxidation
• Combustion of fossil fuel (anthropogenic – around 6-7% loss only)
• Photochemical oxidation
• Fixation of N2 by lightning
• Fixation of N2 by industry (anthropogenic)
• Oxidation of volcanic gases
• Chemical weathering
• Surface reaction of O3

Only 1 is correct.
A primary pollutant is an air pollutant emitted directly from a source. A secondary pollutant is not directly emitted as such, but forms when other pollutants (primary pollutants) react in the atmosphere.
Examples of a secondary pollutant include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight; nitrogen dioxide (NO2), which is formed as nitric oxide (NO) combines with oxygen in the air; and acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water.

2 and 3 are correct.
PM 2.5 is an atmospheric particulate matter of diameter of fewer than 2.5 micrometres, which is around 3 per cent the diameter of a human hair. It causes respiratory problems and reduces visibility. PM 2.5 particles can only be detected with the help of an electron microscope because they are so small. This prevents their dispersion in the atmosphere and increases concentration. The circulatory system, also called the cardiovascular system is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body to provide nourishment.
Due to their smaller size, the PM 2.5 particles can easily bypass the nose and throat and can easily enter the circulatory system. The particles can also lead to cause chronic diseases such as asthma, heart attack, bronchitis and other respiratory problems.

1, 2 and 3 are correct.
Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera.
Kelps have adapted to the severe conditions. These cool water species have special strategies to survive freezing temperatures and long periods of darkness, and even grow under sea ice. In regions with cold, nutrient-rich water, they can attain some of the highest rates of primary production of any natural ecosystem on Earth. Kelp forests also help protect coastlines by decreasing the power of waves during storms and reducing coastal erosion.
Kelp forests throughout the world play an important role in coastal economies, supporting a broad range of tourism, recreational and commercial activities.