exposure to hot weather decrease in physical exercise consumption of bad food infection by a virus
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Over a two-week period, several students complain of feeling sick. Their symptoms include a cough, fever, and a sore throat. What describes the most likely cause of these symptoms?
Possibilities:
- exposure to hot weather
- decrease in physical exercise
- consumption of bad food
- infection by a virus

infection by a virus