Final answer:
The calf is comprised of two major muscles: the gastrocnemius and the soleus, both attaching to the Achilles tendon and facilitating plantar flexion of the foot.
Step-by-step explanation:
The calf is made up of two major muscles: the gastrocnemius and the soleus. When combined with the plantaris, these muscles form what is commonly referred to as the calf. The most superficial and visible muscle is the gastrocnemius, which has two parts referred to as the medial and lateral heads, and these pull upward on the Achilles tendon.
The soleus lies underneath the gastrocnemius and also attaches to the Achilles tendon. The engagement of these muscles allows for plantar flexion of the foot at the ankle, pointing the toes away from the knee.
Therefore, the correct answer to the question is A) Gastrocnemius and soleus.