## Core Concept
Yaws is a tropical disease caused by the bacterium *Treponema pallidum* subspecies *pertenue*. It is characterized by a primary cutaneous lesion (mother yaw) followed by secondary and tertiary stages, with potential for long-term disability if left untreated. The disease is primarily spread through skin contact.

## Why the Correct Answer is Right
The correct answer choice isn't directly provided, but based on common facts about yaws:
- Yaws is indeed caused by *Treponema pallidum* subspecies *pertenue*, similar to syphilis but with different clinical manifestations.
- It is primarily a disease of children in tropical regions.
- The disease can lead to destructive lesions in the skin, bones, and joints.

## Why Each Wrong Option is Incorrect
Without the specific details of options A, B, C, and D, we can still discuss general misconceptions about yaws:
- **Option A:** If a statement claims yaws is caused by a virus, it would be incorrect because yaws is caused by a bacterium.
- **Option B:** If a statement suggests yaws is primarily spread through vectors like mosquitoes, it would be incorrect because it is spread through direct skin-to-skin contact.
- **Option C:** If a statement claims yaws only affects adults, it would be incorrect because it predominantly affects children.
- **Option D:** This would be the correct statement about yaws, making the others incorrect based on the facts about the disease.

## Clinical Pearl / High-Yield Fact
A key point to remember is that yaws is one of the endemic treponematoses, and it can be effectively treated with antibiotics, typically penicillin. The disease is targeted for eradication by the World Health Organization.

## Correct Answer: D.