Assertion (A): Amoeba reproduces by binary fission.
Reason ( R): All unicellular organisms reproduce asexually.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A.
C. A is true but R is false.
D. A is false and R is true.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Amoeba reproduces by binary fission."
- **Explanation**: Binary fission is a form of asexual reproduction where a single organism divides into two parts, each of which becomes a new organism. In the case of amoeba, the process involves the division of its nucleus followed by the division of its cytoplasm.

2. **Understanding the Reason**: The reason states that "All unicellular organisms reproduce asexually."
- **Explanation**: Asexual reproduction is a simpler method of reproduction that is often utilized by unicellular organisms due to their simple structure. Since they consist of only one cell, they typically reproduce by methods like binary fission, budding, or fragmentation, rather than sexual reproduction.

3. **Evaluating the Truth of the Statements**:
- **Assertion**: True. Amoeba indeed reproduces by binary fission.
- **Reason**: True. Most unicellular organisms do reproduce asexually, as sexual reproduction is more complex and not necessary for their survival.

4. **Determining the Relationship**: Now we need to assess if the reason is a correct explanation of the assertion.
- The reason explains why amoeba, being a unicellular organism, reproduces asexually through binary fission. Therefore, the reason supports the assertion.

5. **Conclusion**: Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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