Three of the Following Describe Methods That Researchers Commonly Use

Multiple Choice

Three of the following describe methods that researchers commonly use to determine how the human brain probably functions. Which one is not a commonly used method to study the brain?

A) Documenting the behaviors of people with various kinds of brain injuries
B) Recording brain activity through PET scans, CAT scans, and similar technologies
C) Measuring the levels of various hormones and other substances in the blood
D) Removing a certain part of an animal's brain and observing the animal's subsequent behaviors