Painless open sore called chancre is the characteristic feature of

Options

A. Genital herpes
B. Chancroid
C. Genital wart
D. Syphilis

Answer

To solve the question regarding the painless open sore called chancre, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Term "Chancre":**
- A chancre is defined as a painless ulcer that typically appears in the genital area. It is a significant clinical feature that helps in diagnosing certain sexually transmitted diseases (STDs).

2. **Identifying Diseases Associated with Chancre:**
- We need to consider various diseases that are known to cause painless sores or ulcers. The most notable ones include:
- Genital herpes
- Cancroid
- Genital warts
- Syphilis

3. **Analyzing Each Disease:**
- **Genital Herpes:** Caused by the herpes simplex virus, it is characterized by painful sores, not painless.
- **Cancroid:** Caused by the bacterium Haemophilus ducreyi, it typically presents with painful ulcers and is not associated with painless sores.
- **Genital Warts:** Caused by the human papillomavirus (HPV), these present as bumps rather than open sores.
- **Syphilis:** This disease is known for causing painless sores (chancres) during its primary stage.

4. **Conclusion:**
- Based on the analysis, the disease that is characterized by a painless open sore called chancre is **syphilis**.

### Final Answer:
The painless open sore called chancre is a characteristic feature of **syphilis**.

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