For this question, we are looking for a muscle that lies in the posterior, superficial compartment of the leg. This eliminates the gracilis muscle, leaving the planters, gastrocnemius, and soles muscles. The correct answer is the plantaris muscle which is a small muscle in the posterior compartment of the leg that has a long tendon and little to no function. Both the gastrocnemius and soleus muscles are larger and more important in walking and running.

Because this muscle has its origin on the ischial tuberosity of the pubic bone and inserts into the medial condyle of the tibia, it is a muscle in the thigh. Of the following answer choices only the semimembranosus and the gracilis muscles are located in the thigh. However, its attachments also show that this muscle will be in the posterior compartment of the thing, meaning the correct answer is the semimembranosus muscle.

The correct answer is the iliacus. This is the only one of these muscles that is located in the hip region. The intercostals are between each of the ribs and the pectineus and gracilis muscles in the thighs.

We are looking for a muscle in the posterior compartment of the thigh. This means that the muscle will be on the back of the leg, between the pelvis and the kneecap. The correct answer is the gracilis muscle, which unlike the other three is located in the anterior compartment of the thigh.

Extensor muscles located in the deep, posterior compartment of the leg are responsible for flexing the toes. In this case, the correct answer is the extensor digitorum longus because it controls the 2nd through 5th digits in the feet. We can infer this by looking at the word "digitorum", meaning digits, as in fingers or toes. The extensor hallucis longus extends the first digit in the lower extremity (hallux) and dorsiflexes the foot. The tibialis anterior is the strongest dorsiflexor of the foot.

Although the gastrocnemius is a large muscle, it is not as involved in walking and running as is the soleus. Rather, it is a powerful plantarflexor of the foot and is more active in jumping and other movements that require powerful plantarflexion. The gracilis muscle is located in the thigh, and is responsible for weak flexion, internal rotation, and adduction of the hip. The plantaris muscle only minimally aids in running and walking and is not present in about 10% of the population. This means the correct answer is the soleus muscle.

The quadriceps tendon is located in the anterior compartment of the thigh. This means we are looking for a muscle that is also located in the anterior compartment of the thigh. There are four muscles that insert via the quadriceps tendon: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. 

The gastrocnemius is one of the muscles that makes up the calf muscles in the leg. The other calf muscle is the soleus, which lies under the gastrocnemius. The gastrocnemius also has two heads which give it a "diamond" shape. There are several layers of different muscles on the soles of the feet. The hamstrings are the group of muscles found on the back of the thigh, with the biceps femoris being the largest. The quadriceps are the muscle group on the front of the thigh, the vastus lateralis is the largest of these. 

Sartorius, gracilis, semitendinosus make up the pes anserine group whose conjoined tendons insert onto the anteromedial surface of the proximal extremity of the tibia. They flex and medially rotate the leg at the knee joint. 

The tensor fascia latae attaches from the anterior superior iliac spine to the iliotibial band.