Question

a muscle that inserts on the body of the mandible is involved in
spitting.
chewing.
frowning.
pursing the lips.
blowing.

Explanation:

Muscles inserting on the mandible (lower jaw) are primarily involved in movements of the jaw. Chewing (mastication) requires the contraction of muscles attached to the mandible to move it up and down, side - to - side. Spitting, frowning, pursing the lips, and blowing involve other facial muscles not primarily associated with mandible - inserting muscles.

Answer:

chewing.