Assertion: ELISA is widely used for the detection of infectious diseases like AIDS.
Reason: ELISA is very sensitive and selective test and needs very small amount of reagents.

Options

A. If both Assertion and Reason are true and Reason is correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "ELISA is widely used for the detection of infectious diseases like AIDS."
- ELISA (Enzyme-Linked Immunosorbent Assay) is indeed a common diagnostic tool for detecting antibodies or antigens related to infectious diseases, including HIV, which causes AIDS.

2. **Understanding the Reason:**
- The reason provided is that "ELISA is a very sensitive and selective test and needs a very small amount of reagents."
- ELISA is known for its sensitivity and specificity in detecting specific antibodies or antigens, which is crucial for accurate diagnosis. It also typically requires small amounts of reagents.

3. **Evaluating the Truth of Assertion and Reason:**
- Both the assertion and the reason are true statements. However, the reason does not provide a correct explanation for the assertion. The assertion is about the application of ELISA in diagnosing AIDS, while the reason describes its sensitivity and reagent requirements.

4. **Conclusion:**
- Since the assertion is true and the reason is also true but does not correctly explain the assertion, the correct answer is that the assertion is true, and the reason is false.

**Final Answer:**
- The assertion is true, and the reason is false.

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