Assertion (A): Both AIDS and Hepatitis B are infectious viral diseases.
Reason (R): Both the diseases are transmitted by vectors.

Options

A. Both A and R are true and R is the correct explanation for A.
B. Both A and R are true, but R is not the correct explanation for A.
C. A is true and R is false.
D. A is false and R is true.

Explanation

To analyze the assertion and reason provided in the question, we will break down each part systematically.

### Step 1: Analyze the Assertion (A)
The assertion states that both AIDS and Hepatitis B are infectious viral diseases.

- **AIDS**: This disease is caused by the Human Immunodeficiency Virus (HIV), which attacks the immune system, making the body more susceptible to infections and diseases.
- **Hepatitis B**: This disease is caused by the Hepatitis B virus (HBV), which primarily affects the liver and can lead to serious liver conditions.

**Conclusion**: The assertion is **true** because both AIDS and Hepatitis B are indeed infectious viral diseases.

### Step 2: Analyze the Reason (R)
The reason states that both diseases are transmitted by vectors.

- **Vectors**: In biological terms, vectors are organisms that transmit pathogens from one host to another. Common examples include mosquitoes (for malaria) and ticks (for Lyme disease).
- **Transmission of AIDS and Hepatitis B**: Both diseases are primarily transmitted through direct contact with infected body fluids (such as blood, semen, and vaginal fluids) and not through vectors. They can be spread through sexual contact, sharing needles, or from mother to child during childbirth.

**Conclusion**: The reason is **false** because neither AIDS nor Hepatitis B is transmitted by vectors; they are transmitted through direct contact with infected fluids.

### Final Conclusion
- The assertion (A) is true.
- The reason (R) is false.

### Overall Answer
The correct interpretation of the assertion and reason is that while both AIDS and Hepatitis B are infectious viral diseases, they are not transmitted by vectors. Therefore, the assertion is true, but the reason is false.

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