## Core Concept
The tongue muscles are primarily derived from the occipital myotome, which is a group of somites that give rise to the intrinsic and extrinsic muscles of the tongue. However, one muscle of the tongue is known to develop from a different origin.

## Why the Correct Answer is Right
The muscle of the tongue that is NOT developed from the occipital myotome is the **palatoglossus**. The palatoglossus muscle is one of the muscles of the palate and is derived from the **6th pharyngeal arch**, which contributes to the formation of the intrinsic muscles of the larynx and some muscles of the pharynx and palate, including the palatoglossus. This is in contrast to the other muscles of the tongue, which are derived from the occipital somites.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is incorrect because the specific muscle names are not provided, making it impossible to directly assess its accuracy. However, based on the correct answer being , we can infer that the other options are muscles derived from the occipital myotome.
- **Option B:** Similarly, without specific details, we acknowledge that this option represents a muscle derived from the occipital myotome, contrasting with the correct answer.
- **Option C:** This option is also incorrect for the same reason as Option A, implying that the muscle listed here develops from the occipital myotome.

## Clinical Pearl / High-Yield Fact
A key point to remember is that the **palatoglossus** muscle, involved in elevating the posterior part of the tongue and in the initiation of swallowing, is unique among the tongue muscles due to its different embryological origin. This distinction is crucial for understanding the complex innervation and function of the tongue.

## Correct Answer: D. Palatoglossus.