What is a psychologist? needs to be answered asap
1. a person who studies how the brain functions
2. a person who runs medical tests on the brain
3. a person who studies how people think, feel, and behave
4. a person who performs brain surgery

A psychologist is a person who studies how people think, feel, and behave

Explanation:

A psychologist studies normal and abnormal mental states, perceptual, cognitive, emotional, and social processes and behavior by experimenting with, and observing, interpreting, and recording how individuals relate to one another and to their environments.

i think it's the first one because doctors aren't the ones who get rid of the old needles. most of them time it's not even doctors who give you shots, it's nurses.