Skeletal muscles:
a. work in antagonistic pairs
b. all have fixed origins and insertions
c. are named only for their locations
d. all of the above

The correct answer is option D. all of the above.

Explanation:

The skeletal muscle is a type of striated muscle, that is controlled by the somatic nervous system. Tendons are the collagen fiber that binds these muscles to the bones.

Skeletal muscles are arranged in antagonistic pairs so if a muscle helps a joint to move so the other muscle can bring it to its original resting position. The point where muscle binds to an immovable bone called the origin of the muscle and the point where muscle attached to a movable bone its termed as insertion.

Thus, the correct answer is option D.

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