**Core Concept**
Fox Fordyce's disease is a rare skin disorder characterized by the blockage of apocrine glands, leading to the formation of small, itchy bumps on the skin, particularly in the armpits and groin area. This condition is caused by the abnormal functioning of apocrine glands, which are a type of sweat gland. The blockage of these glands results in the accumulation of keratin and other substances, leading to the characteristic skin lesions.

**Why the Correct Answer is Right**
The correct answer is related to the apocrine glands, which are responsible for the production of a type of sweat that is rich in protein and lipids. In Fox Fordyce's disease, the apocrine glands become blocked, leading to the accumulation of keratin and other substances. This blockage causes the glands to become distended, leading to the formation of small, itchy bumps on the skin. The apocrine glands are located in the armpits and groin area, making these regions particularly prone to the development of Fox Fordyce's disease.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Fox Fordyce's disease is not related to eccrine glands, which are a different type of sweat gland that produces a clear, watery sweat.

**Option B:** This option is incorrect because Fordyce's spots are a different condition that is characterized by the presence of small, yellowish spots on the lips or inside the cheeks, and are not related to Fox Fordyce's disease.

**Option C:** This option is incorrect because keratosis pilaris is a condition that is characterized by the presence of small, rough bumps on the skin, but it is not related to the blockage of apocrine glands.

**Option D:** This option is incorrect because hidradenitis suppurativa is a condition that is characterized by the presence of painful, inflamed nodules on the skin, particularly in the armpits and groin area, but it is not related to the blockage of apocrine glands.

**Clinical Pearl / High-Yield Fact**
Fox Fordyce's disease is often misdiagnosed as eczema or dermatitis, but it is a distinct condition that requires specific treatment. Treatment options for Fox Fordyce's disease include topical creams and ointments, as well as surgical excision of the affected glands.

**Correct Answer: B. Fordyce's spots.**