Answer:
A.
Explanation:
Synergist muscles are those muscles in body that helps or are responsible to help the same set of joint in action. They tend to serve as agonist. This muscles helps to act or produce action around a moveable joint.
An example of synergist muscle is biceps brachii that helps to perform actions in forearm flexion. a synergist can also serve as a fixator at the muscles origin.
Therefore, the correctanswer is option A.