**Core Concept:** Cutaneous larva migrans is a skin infection caused by the larvae of certain parasitic worms, most commonly the hookworms (Ancylostoma, Necator, or Uncinaria species).

**Why the Correct Answer is Right:** Cutaneous larva migrans develops when the larvae of parasitic worms, specifically hookworms, penetrate the skin and migrate through the dermal and subcutaneous layers. These larvae are often introduced to the skin through accidental penetration by the larvae when the skin comes into contact with contaminated soil. The larvae then migrate to the dermal layer, causing a series of migratory lesions.

**Why Each Wrong Option is Incorrect:**

A. Option A (Nematodes) is partially correct, but only hookworms are responsible for cutaneous larva migrans, not all nematodes.
B. Option B (Intestinal Parasites) is incorrect because cutaneous larva migrans is caused by the larvae entering the skin, not the intestines.
C. Option C (Tropical Diseases) is partially correct, but cutaneous larva migrans is a specific skin infection caused by hookworm larvae, not a broader category of tropical diseases.
D. Option D (Infection Due to Roundworms) is incorrect because cutaneous larva migrans is specifically caused by hookworm larvae, not all roundworm infections.

**Clinical Pearl:** A clinical pearl that students should not forget is that the larvae of hookworms (Ancylostoma, Necator, or Uncinaria species) are responsible for cutaneous larva migrans due to accidental penetration of the skin and subsequent migration through dermal and subcutaneous layers. This infection is typically seen in tropical regions where these worms are commonly found in soil contaminated with feces.

**Correct Answer:** D. Infection Due to Roundworms (Option D) is the correct answer as cutaneous larva migrans is caused by the larvae of hookworms, which are roundworms. Cutaneous larva migrans represents a specific skin infection, not a general infection due to roundworms.