What is the action of the frontalis?

Name the muscles labeled B[B], C[C], and D[D].

Name the muscles labeled A, B, and D.

Identify the muscles labeled A, B, and C.

Name the muscles labeled A, B, C, and D.

Name the muscles labeled A, C, and D.

Name the muscle labeled A[A] and B[B].

Name the muscles labeled C and D.

Name two other muscles you have not mentioned already.

What is the action of the biceps brachii?