Which of the Following Best Describes a Sphincter Muscle

Question

Which of the following best describes a sphincter muscle?
A) Oblique
B) Encircle
C) Straight
D) Aponeurosis

Accepted Answer

A sphincter muscle is a circular muscle that encircles an opening or tube in the body and can contract or relax to control the flow of substances through that opening. Examples include the anal sphincter, which controls the release of feces from the rectum, and the esophageal sphincter, which prevents gastric acid from refluxing up into the throat.