Which of the following would result in increase in "Global warming"?

• Increase in carbon dioxide in the atmosphere
• Burning of fossil fuels in the environment
• Increase in methane in the atmosphere

1, 2 and 3

The correct answer is option 4: 1, 2 and 3

All the listed factors contribute to global warming:

1. Increase in carbon dioxide in the atmosphere - Carbon dioxide is a major greenhouse gas that traps heat in the atmosphere, contributing to global warming.
2. Burning of fossil fuels in the environment - This process releases carbon dioxide and other greenhouse gases into the atmosphere, increasing global warming.
3. Increase in methane in the atmosphere - Methane is a potent greenhouse gas that also contributes to global warming.