What is the primary function of the Achilles tendon?

The primary function of the Achilles tendon is to facilitate foot plantarflexion, which is the movement that occurs when the foot is pointed downwards, such as during walking, running, or jumping. This tendon connects the calf muscles (gastrocnemius and soleus) to the heel bone (calcaneus) and plays a critical role in enabling the powerful push-off phase of these activities.

When the calf muscles contract, they pull on the Achilles tendon, which in turn lifts the heel and allows the forefoot to push off the ground. This function is essential for movements that require propulsion, balance, and stability during various physical activities and sports.

The other choices relate to different joints and muscles not directly connected to the critical action performed by the Achilles tendon, emphasizing why they do not represent its primary function.