Part of the quadriceps group of muscles

a. Rectus femoris

b. rectus abdominis

A. Rectus femoris

Explanation:

Rectus femoris is one of the muscles of the Quadriceps femoris group which in turn makes the anterior and posterior thigh. The rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis together make the quads. Rectus femoris is the thigh muscle that originates from the ilium. It is an example of bipennate muscle and has central tendons. Fascicles are located on either side of the tendons.