Statement 1 is correct while statement 2 is incorrect.
In economics, the GDP deflator is a measure of the level of prices of all new, domestically produced, final goods and services in an economy in a year. Like the consumer price index (CPI), the GDP deflator is a measure of price inflation/deflation with respect to a specific base year.
When GDP deflator is negative, nominal GDP is less than real DP. It means that there is deflation in the economy.

Both the statements are correct.
Monetary policy refers to the policy of the central bank with regard to the use of monetary instruments under its control to achieve the goals specified in the Act. The Reserve Bank of India (RBI) is vested with the responsibility of conducting monetary policy. This responsibility is explicitly mandated under the Reserve Bank of India Act, 1934.
The primary objective of monetary policy is to maintain price stability while keeping in mind the objective of growth. Price stability is a necessary precondition to sustainable growth.

Both the statements are incorrect.
Council of Ministers are collectively responsible to the Lok Sabha.
Chairman of Rajya Sabha cannot preside over a joint sitting of the two houses of the Parliament in any circumstance. It the Lok Sabha speaker who presides over such a meeting.

Statement 1 is correct while statement 2 is incorrect.
OPCW is an intergovernmental organisation and the implementing body for the Chemical Weapons Convention. This convention is in force since 1997 and 193 members.
It has 193 members including India. It is headquartered in the Hague, Netherlands.
The OPCW was awarded the Nobel Peace Prize in 2013.

Statement 1 is correct while statement 2 is incorrect.
The debt-to-GDP ratio is the metric comparing a country’s public debt to its gross domestic product (GDP). By comparing what a country owes with what it produces, the debt-to-GDP ratio reliably indicates that particular country’s ability to pay back its debts.
Statement 2 is incorrect. As per Reserve Bank of India Act of 1934, the Reserve Bank is both the banker and public debt manager for the Union government. However, of late, there is a demand for creating a specialized agency for managing public debt as exists in some advanced economies. For instance, the NITI Aayog has advocated the creation of a separate public debt management agency (PDMA).