Ring worn infection affects –
**Core Concept**
The question is testing knowledge of a specific type of infection affecting the skin, known as a ringworm infection. Ringworm is a fungal infection caused by dermatophytes, which invade and damage the outer layer of the skin, hair, and nails.
**Why the Correct Answer is Right**
Ringworm infections primarily affect the skin, causing a characteristic ring-shaped rash. The dermatophytes responsible for this infection, such as Trichophyton, Microsporum, and Epidermophyton, feed on keratin, a protein found in skin, hair, and nails. The infection spreads through direct contact with an infected person or contaminated surface, and it can also be transmitted by animals, such as cats and dogs. The correct answer is related to the primary site of infection.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because ringworm infections do not primarily affect the respiratory system.
**Option B:** This option is incorrect because ringworm infections do not primarily affect the gastrointestinal system.
**Option C:** This option is incorrect because while ringworm infections can affect the nails, they primarily affect the skin.
**Clinical Pearl / High-Yield Fact**
Ringworm infections are highly contagious and can be spread through direct contact with an infected person or contaminated surface. It's essential to practice good hygiene, such as washing hands frequently and avoiding sharing personal items, to prevent the spread of this infection.
**Correct Answer:** D. Skin