What is this muscle

In an antagonistic muscle pair as one muscle contracts the other muscle relaxes or lengthens. The muscle that is contracting is called the

In an antagonistic muscle pair as one muscle contracts the other muscle relaxes or lengthens. The muscle that is relaxing or lengthening is called the

The antagonistic muscle of the rectus abdominis is the

The insertion of the deltoid is the:

What are the antagonistic muscle for the Pectoralis major

Select the muscle highlighted.

Select the muscle that is highlighted.

What are the group of muscles in the picture?

What are the group of muscles in the picture?

What is the highlighted muscle in the picture

What is the highlighted muscle in the picture?