pneumonia caused by microorganisms heart problem caused by a high-fat diet lung cancer caused by smoking eye damage caused by ultraviolet light
I gave my students this multiple choice question: Which health condition is an infectious disease?

Only one answer is correct among these 4 choices:
- pneumonia caused by microorganisms
- heart problem caused by a high-fat diet
- lung cancer caused by smoking
- eye damage caused by ultraviolet light

Could you tell me which one is correct?

pneumonia caused by microorganisms