Assertion: Syphilis spreads by sexual intercourse with infected persons.
Reason: Syphilis is caused by Spirochaete bacterium, Treponema pallidum.

Options

A. If both Assertion and Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertin and Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true but Reason is false, then mark (3).
D. If both Assertion and Reason are false. Then mark (4).

Answer

To solve the question regarding the assertion and reason about syphilis, we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states that "Syphilis spreads by sexual intercourse with infected persons."
- **Explanation**: Syphilis is classified as a sexually transmitted disease (STD). It is primarily transmitted through sexual contact with an infected individual. This means that if a person engages in sexual activity with someone who has syphilis, they are at risk of contracting the disease.

### Step 2: Understand the Reason
The reason states that "Syphilis is caused by Spirochaete bacterium, Treponema pallidum."
- **Explanation**: Syphilis is indeed caused by a specific bacterium known as Treponema pallidum, which is a type of spirochete. This bacterium is responsible for the symptoms and progression of the disease.

### Step 3: Analyze the Relationship Between Assertion and Reason
Now, we need to determine if the reason provided explains the assertion.
- **Explanation**: While both the assertion and reason are true, the reason does not explain why syphilis spreads through sexual intercourse. The assertion focuses on the mode of transmission, while the reason provides information about the causative agent of the disease.

### Conclusion
Both the assertion and reason are correct statements:
- Assertion: True
- Reason: True
However, the reason does not serve as an explanation for the assertion.

### Final Answer
The correct answer is: Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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