Q: What do the muscles of the gastrointestinal tract do?


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

Organs of the GI tract are covered by muscles that contract to keep food moving along. A series of involuntary muscle contractions moves rapidly along the tract, like a wave travelling through a spring toy. The muscle contractions are called peristalsis. The diagram in Figure below shows how peristalsis works.

 Choices:

- break down food

- secrete stomach acid

- stop digestion

- keep food moving


A:
keep food moving