**Core Concept**
Perifascicular atrophy refers to the selective atrophy of muscle fibers at the periphery of the fascicle, a characteristic histopathological feature. This phenomenon is often associated with muscle diseases that involve inflammation and damage to the muscle tissue.

**Why the Correct Answer is Right**
Dermatomyositis is a type of inflammatory muscle disease characterized by skin rash and muscle weakness. In dermatomyositis, perifascicular atrophy is a hallmark histological feature, resulting from the inflammatory damage to the muscle fibers at the periphery of the fascicle. This damage is mediated by the immune system's attack on the muscle tissue, leading to the characteristic atrophy. The perifascicular location of the atrophy is thought to be due to the relative sparing of the central fibers, which are more resistant to the inflammatory damage.

**Why Each Wrong Option is Incorrect**
**Option A:** Duchenne muscular dystrophy is a genetic disorder that leads to progressive muscle degeneration, but it is not typically associated with perifascicular atrophy. Instead, Duchenne muscular dystrophy is characterized by widespread muscle fiber degeneration and replacement with fat and connective tissue.

**Option B:** Wilson disease is a genetic disorder that leads to copper accumulation in the body, particularly in the liver and brain. While Wilson disease can cause muscle weakness and tremors, it is not typically associated with perifascicular atrophy.

**Option C:** Becker's muscular dystrophy is a genetic disorder that is similar to Duchenne muscular dystrophy, but it is milder and progresses more slowly. Like Duchenne muscular dystrophy, Becker's muscular dystrophy is not typically associated with perifascicular atrophy.

**Clinical Pearl / High-Yield Fact**
Perifascicular atrophy is a key histological feature of dermatomyositis, and its presence can help differentiate this condition from other muscle diseases. It is essential to consider the clinical context and histological findings when diagnosing muscle diseases.

**✓ Correct Answer: D. Dermatomyositis**