a reduction in the ozone layer a reduction in photosynthesis an increase in radioactive wastes an increase in the greenhouse effect
I gave my students this multiple choice question: Which of these is most likely an effect of releasing carbon dioxide pollution into the atmosphere?

Only one answer is correct among these 4 choices:
- a reduction in the ozone layer
- a reduction in photosynthesis
- an increase in radioactive wastes
- an increase in the greenhouse effect

Could you tell me which one is correct?

an increase in the greenhouse effect