Q: What part of the muscle fibers cause shortening and contraction?


Read this paragraph and choose the correct option from the provided answers:

The sliding-and-shortening process occurs all along many myofibrils and in many muscle fibers. It causes the muscle fibers to shorten and the muscle to contract.

 Choices:

- fasciae

- pores

- collagen

- myofibrils


A:
myofibrils