The options to choose from are: portal of exit, reservoir, portal of entry
The answers are JoAnn is the reservoir in the chain of transmission. The mucus from her cough is the portal of exit in the chain of transmission.
JoAnn is the reservoir because the cold is stored in her body. The mucus is the portal of exit because it is being coughed up outside the body.
Very true.
Milk is a protein and builds up the body.
