Please see the question below. Scroll down for the correct answer and video explanation.
KNAT Practice Test Answer Explanation
The correct answer is A. 2. Muscles must work in pairs to move bones at the joint. The muscle that causes a joint to bend is called a flexor muscle. The muscle that contracts and causes a joint to straighten is called an extension muscle. If one muscle in the pair contracts, the other remains elongated.
For a review on the muscular system, watch the answer explanation video below.
[Source: KNAT Tutor Lesson: Support & Movement]