**Core Concept**
Heel raising movement, also known as toe-off or plantarflexion, is a fundamental aspect of gait mechanics. It involves the contraction of the gastrocnemius and soleus muscles, facilitated by the Achilles tendon, to lift the heel off the ground during the push-off phase of walking.

**Why the Correct Answer is Right**
The heel raising movement is primarily prevented by the **Achilles tendon**, which functions as a passive link between the gastrocnemius and soleus muscles. When the calf muscles contract, the Achilles tendon transmits the force to the heel bone, enabling plantarflexion. In the context of a Removable Partial Denture (RPD), the presence of the denture base and its attachments may interfere with the normal functioning of the Achilles tendon, thereby preventing heel raising movement.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the heel raising movement, as it does not involve the calf muscles or the Achilles tendon.
* **Option B:** While the foot's intrinsic muscles play a role in maintaining balance and stability, they do not directly contribute to the heel raising movement.
* **Option C:** This option is incorrect, as the ankle joint's mobility is not directly responsible for preventing heel raising movement.

**Clinical Pearl / High-Yield Fact**
In the context of RPDs, the design and placement of the denture base can significantly affect the patient's gait mechanics. A well-designed RPD should minimize interference with the normal functioning of the calf muscles and the Achilles tendon to maintain optimal gait efficiency.

**Correct Answer:** C.