Assertion : Nucleic acid complexes alone cannot cause diseases.
Reason : Only nucleoproteins can function as infectious agents.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To analyze the assertion and reason provided in the question, we can break it down step by step:

### Step 1: Understand the Assertion
- **Assertion:** "Nucleic acid complexes alone cannot cause diseases."
- **Analysis:** Nucleic acids, which include DNA and RNA, can indeed cause diseases. For example, certain viruses that have RNA or DNA as their genetic material can lead to infections and diseases in hosts. Therefore, the assertion is **incorrect**.

### Step 2: Understand the Reason
- **Reason:** "Only nucleoproteins can function as infectious agents."
- **Analysis:** This statement is also misleading. While nucleoproteins (complexes of nucleic acids and proteins) can act as infectious agents (like viruses), they are not the only type of infectious agents. Other entities, such as viroids (which are infectious RNA molecules without protein coats), can also cause diseases. Thus, the reason is also **incorrect**.

### Step 3: Conclusion
- Since both the assertion and the reason are incorrect, we conclude that the correct answer is that both statements are false.

### Final Answer:
Both the assertion and reason are false.

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