Consider the following statements: 1. Kyoto Protocol came into force in the year 2005. 2. Kyoto Protocol deals primarily with the depletion of the Ozone layer. 3. Methane as a greenhouse gas is more harmful than carbon dioxide. Which of the statements is/are correct?

The correct answer is Option 2 (1 and 3) based on the following analysis:

• Statement 1 is correct: Although adopted in 1997, the Kyoto Protocol officially came into force on February 16, 2005, after the ratification by the Russian Federation fulfilled the "55% emission" clause.
• Statement 2 is incorrect: The Kyoto Protocol is an international treaty under the UNFCCC aimed at reducing greenhouse gas emissions to combat global warming. Issues regarding the depletion of the Ozone layer are addressed by the Montreal Protocol (1987).
• Statement 3 is correct: Methane (CH4) is a significantly more potent greenhouse gas than Carbon Dioxide (CO2). It has a Global Warming Potential (GWP) over 25-28 times higher than CO2 over a 100-year period, making it more "harmful" in terms of heat-trapping efficiency.

Since statements 1 and 3 are factually accurate while statement 2 is conceptually misplaced, Option 2 is the right choice.