## **Core Concept**
The anterior compartment of the leg is primarily responsible for dorsiflexion of the foot and toes. The nerve supply to this compartment is crucial for its motor and sensory functions. The **common peroneal nerve** (also known as the common fibular nerve) and its branches are key to understanding the innervation of the leg's anterior compartment.

## **Why the Correct Answer is Right**
The **deep peroneal nerve (D)** is a branch of the common peroneal nerve. It is responsible for innervating the muscles in the anterior compartment of the leg, which include the tibialis anterior, extensor digitorum longus, and extensor hallucis longus. These muscles are involved in ankle dorsiflexion and toe extension. The deep peroneal nerve also provides sensation to the area between the first and second toes.

## **Why Each Wrong Option is Incorrect**
- **Option A:** The **tibial nerve** primarily supplies the posterior compartments of the leg, which are involved in plantarflexion and inversion of the foot. It is not responsible for the innervation of the anterior compartment.
- **Option B:** The **superficial peroneal nerve** is another branch of the common peroneal nerve but it primarily innervates the muscles of the lateral compartment of the leg (peroneus longus and peroneus brevis), which are involved in foot eversion.
- **Option C:** The **saphenous nerve** is a purely sensory nerve that originates from the femoral nerve. It provides sensory innervation to the medial aspect of the leg but does not innervate any muscles in the anterior compartment.

## **Clinical Pearl / High-Yield Fact**
A key clinical correlation to remember is that damage to the deep peroneal nerve can lead to **foot drop**, a condition where the patient is unable to dorsiflex the foot. This often results in a steppage gait to avoid tripping over the toes.

## **Correct Answer: D. Deep peroneal nerve**