## **Core Concept**
The question tests knowledge of muscles involved in the gait cycle, specifically during the stance and swing phases of walking. The gait cycle consists of two main phases: stance (when the foot is on the ground) and swing (when the foot is off the ground). Different muscle groups are activated during these phases to maintain posture, balance, and propulsion.

## **Why the Correct Answer is Right**
The muscle primarily used during both the stance and swing phases of a normal walk is **Tibialis Anterior**. This muscle plays a crucial role in controlling the foot's movement. During the stance phase, it helps in stabilizing the ankle and supporting the medial arch of the foot. In the swing phase, it aids in dorsiflexion of the foot, ensuring that the toes clear the ground. This action is essential for a smooth gait.

## **Why Each Wrong Option is Incorrect**
- **Option A:** While muscles like **Gastrocnemius** and **Soleus** are crucial for walking, particularly in the stance phase for propulsion (via plantarflexion), they are not primarily involved in both stance and swing phases in the same way **Tibialis Anterior** is.
- **Option B:** This option might refer to other muscles, but without specific naming, it's hard to directly refute. However, muscles like **Peroneus Longus** and **Peroneus Brevis** are more involved in lateral ankle stability and foot eversion rather than the functions described.
- **Option D:** This could potentially refer to **Hamstrings** or other hip muscles, which are more involved in the swing phase for hip extension and knee flexion but are not primarily responsible for the fine motor control of the foot during both phases of gait.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that weakness in **Tibialis Anterior** can lead to a condition known as **foot drop**, where the individual has difficulty dorsiflexing the foot, resulting in a characteristic "steppage" gait to compensate. This highlights the muscle's critical role in normal ambulation.

## **Correct Answer:** . Tibialis Anterior