**Core Concept**
Systemic infections are caused by fungi that can invade and disseminate through the bloodstream, affecting multiple organs and systems in the body. This occurs primarily in immunocompromised individuals or those with underlying medical conditions that compromise the integrity of the skin and mucous membranes.

**Why the Correct Answer is Right**
Dermatophytes, such as Trichophyton, Microsporum, and Epidermophyton, are a type of fungi that primarily cause superficial skin infections like tinea pedis (athlete's foot), tinea corporis (ringworm), and onychomycosis (fungal nail infections). They do not typically cause systemic infections because they are unable to penetrate the skin and invade deeper tissues. In contrast, other fungi like Cryptococcus, Histoplasma, and Paracoccidioides are known to cause systemic infections by invading the bloodstream and affecting multiple organs.

**Why Each Wrong Option is Incorrect**
**Option A:** Cryptococcus neoformans is a type of encapsulated yeast that can cause systemic infections, particularly in immunocompromised patients, by invading the lungs, central nervous system, and other organs.
**Option B:** Histoplasma capsulatum is a dimorphic fungus that can cause systemic histoplasmosis, affecting the lungs, spleen, liver, and bone marrow in immunocompromised individuals.
**Option D:** Paracoccidioides brasiliensis is a dimorphic fungus that causes paracoccidioidomycosis, a systemic infection affecting the lungs, skin, and other organs in immunocompromised patients.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that while dermatophytes primarily cause superficial skin infections, other fungi can cause systemic infections in immunocompromised patients. Early recognition and treatment of these systemic infections are critical to prevent complications and improve patient outcomes.

**Correct Answer:**
✓ Correct Answer: C. Dermatophytes