The flu is a disease caused by the flu virus. Many other diseases, like pneumonia, are caused by bacteria. Do all microorganisms cause harm to the human body?
A) No, only the flu virus can cause harm to the human body.
B) No, many microorganisms, like those in your gut, are beneficial.
C) Yes, any microorganism that enters your bloodstream will be harmful.
D) Yes, any microorganism that comes in contact with your skin will be harmful.
