Answer: B. deforestation and the burning of fossil fuels.
Step-by-step explanation:
Global warming is a phenomena of rise in global temperatures due to certain human activities and natural processes like volcanic eruption.
The burning of fossil fuels and deforestation are the examples of human activities which contribute to global warming. These two activities increase the abundance of greenhouse gases like methane, carbon monoxide, carbon dioxide, nitrous oxides, sulphur oxides in the atmosphere. These gases trap the heat energy from sunlight and increase the temperature of the atmosphere. Hence, are responsible for global warming.