Question

which action is provided by contraction of the triceps brachii?
o abduction of the humerus
o extension of the forearm
o extension of the humerus
o supination of the forearm

Explanation:

The triceps brachii is a muscle on the back of the upper - arm. Its main function is to extend the forearm at the elbow joint. Abduction of the humerus is mainly done by other shoulder muscles, extension of the humerus is not its primary action, and supination of the forearm is mainly by the supinator muscle.

Answer:

Extension of the forearm