The skeletal muscles are involved in the movement and actions. The myofibril initiates the contraction to make the whole muscle contract. Thus, option A is correct.
What is myofibril?
Myofibril is an organelle of the muscle cells that makes the muscle fibers of the skeletal muscles. The myofibril comprises myofilaments that are responsible for appearance and movement.
The myosin is the thick myofilament and actin is the thin myofilament that comprises the sarcomere that brings about the contraction by sliding over each other.
Therefore, the myofilaments (actin and myosin) of myofibril bring about the contraction of the muscles.
Learn more about myofibril here:
https://brainly.com/question/27960162
#SPJ2
