Assertion : Barley ,Sorghum , and millet are smoother crops.
Reason : they factor the growth of some common weeds.

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 Assertion 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 false , then mark(3).
D. If both assertion is true Reason are false , then Mark (4).

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Barley, Sorghum, and Millet are smoother crops."
- Smoother crops are defined as crops that grow thickly and rapidly, which helps in suppressing the growth of weeds.

2. **Understanding the Reason**:
- The reason given is that "they factor the growth of some common weeds."
- This implies that these crops promote or allow the growth of weeds, which contradicts the definition of smoother crops.

3. **Evaluating the Assertion**:
- Barley, Sorghum, and Millet are indeed considered smoother crops because they have a robust growth pattern that can outcompete weeds for resources like water and nutrients.

4. **Evaluating the Reason**:
- The reason is incorrect. Smoother crops do not promote the growth of weeds; instead, they inhibit it by competing for resources.

5. **Conclusion**:
- Since the assertion is true (Barley, Sorghum, and Millet are smoother crops) and the reason is false (they do not factor the growth of weeds), we conclude that the correct answer is option 3: "Assertion is true but reason is false."

### Final Answer:
The correct answer is option 3.

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