**Core Concept**
The question refers to the effect of Dystonia Torsion Cervicalis (DTC) on various muscles, specifically which one is affected last. DTC is a form of focal dystonia characterized by involuntary muscle contractions leading to abnormal postures.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's discuss the general approach to understanding which muscle might be affected last in DTC. In DTC, the muscles of the neck are primarily involved, including the sternocleidomastoid and the splenius capitis. The progression of the disease can vary, but typically, the sternocleidomastoid muscle is one of the first to be affected due to its significant role in neck movement.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific details of the options, it's challenging to provide a precise explanation for why each might be incorrect. However, in the context of DTC, muscles like the sternocleidomastoid are often affected early due to their role in neck rotation and lateral flexion.
**Option B:** Similarly, without the specific option details, we can't directly address why this choice is incorrect. Generally, muscles involved in the pathology of DTC are those responsible for the movement and stabilization of the head and neck.
**Option C:** This option's incorrectness would depend on the muscle in question. If it's a muscle not typically involved in the early stages of DTC, it might be considered a plausible candidate for being affected last.
**Option D:** The incorrectness of this option would also depend on the specific muscle listed and its role in the pathophysiology of DTC.

**Clinical Pearl / High-Yield Fact**
A key point to remember in the management of DTC is the potential role of botulinum toxin injections in relieving symptoms by temporarily paralyzing the affected muscles. Understanding the muscles involved and their order of affection can guide treatment strategies.

**Correct Answer:** Not provided in the query.