Question

question 45
1 point
all of the following sphincter muscles throughout the alimentary canal are under involuntary control except:
a lower esophageal
b ileocecal
c internal anal
d external anal

Explanation:

The lower esophageal, ileocecal, and internal anal sphincters are under involuntary control. The external anal sphincter is under voluntary control, allowing for conscious control of defecation.

Answer:

D. External anal