## Core Concept
The primary muscles responsible for tongue movements are extrinsic and intrinsic muscles. **Protrusion of the tongue** refers to the movement where the tongue is thrust forward out of the mouth. This action is mainly facilitated by specific extrinsic muscles of the tongue.

## Why the Correct Answer is Right
The correct answer, **Genioglossus**, is right because this muscle is primarily responsible for protruding the tongue. The **genioglossus** muscle is an extrinsic muscle of the tongue that originates from the superior part of the mental spine of the mandible (genial tubercle) and fans out to insert into the tongue. When it contracts, it helps to protrude the tongue. This muscle works bilaterally for protrusion and unilaterally for tongue deviation.

## Why Each Wrong Option is Incorrect
- **Option A:** The **Hyoglossus** muscle helps in depression and retraction of the tongue, not protrusion.
- **Option B:** The **Palatoglossus** muscle elevates the posterior part of the tongue and aids in initiation of swallowing, not protrusion.
- **Option D:** The **Styloglossus** muscle retracts and elevates the tongue, not responsible for protrusion.

## Clinical Pearl / High-Yield Fact
A useful clinical correlation to remember is that during the neurological examination, if a patient is asked to protrude their tongue and it deviates to one side, it indicates weakness of the genioglossus muscle on the side to which the tongue deviates. This can be a sign of a lower motor neuron lesion.

## Correct Answer: C. Genioglossus