Assertion: Amoeba is known as immortal.
Reason: Amoeba has rigid protective layer around it.

Options

A. (a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
B. (b) If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.
C. (c) If Assertion is true but the Reason is false.
D. (d) If both Assertion and Reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Amoeba is known as immortal." This is based on the fact that amoeba reproduces asexually by binary fission, where the parent cell divides into two daughter cells.

2. **Explaining Binary Fission**: In binary fission, the nucleus of the amoeba divides first, followed by the division of the cytoplasm. This results in the formation of two new amoeba cells. The original parent cell does not undergo natural death; instead, it simply splits into two, and thus, its identity is lost.

3. **Conclusion on Immortality**: Since the parent cell does not age or die in a traditional sense, and instead gives rise to new cells, amoeba is often referred to as "immortal." The cells themselves do not die; they continue to reproduce indefinitely.

4. **Understanding the Reason**: The reason states that "Amoeba has a rigid protective layer around it." This is incorrect because amoeba does not have a rigid protective layer like a cell wall. Instead, it has a flexible cell membrane.

5. **Clarifying the Structure of Amoeba**: The cell membrane of amoeba is not rigid; it allows for flexibility and movement. Rigid protective layers are characteristic of plant cells (cell walls), but amoeba, being a protozoan, lacks this structure.

6. **Final Evaluation**: Since the assertion is true (amoeba can be considered immortal due to its method of reproduction), but the reason is false (amoeba does not have a rigid protective layer), the correct answer is that the assertion is true, but the reason is false.

**Final Answer**: The correct option is C: Assertion is true, but the reason is false.

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