A: Zygote is the first cell of the new ganeration in all sexually reproducing organisms.
R: Cell division and cell differentiation are the stages of embryogenesis.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statements but Reason is false then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Zygote is the first cell of the new generation in all sexually reproducing organisms."
- In sexual reproduction, two gametes (male and female) fuse during fertilization to form a zygote.
- This zygote contains genetic material from both parents and is indeed the first cell of the new generation.

2. **Understanding the Reason (R)**:
- The reason states that "Cell division and cell differentiation are the stages of embryogenesis."
- After the formation of the zygote, it undergoes a series of cell divisions (mitosis) and differentiations to develop into an embryo.
- Embryogenesis is the process that leads to the formation of an embryo from the zygote, which involves both cell division and differentiation.

3. **Evaluating the Truth of the Statements**:
- Both the assertion and the reason are true statements.
- The assertion correctly identifies the zygote as the first cell of a new generation.
- The reason accurately describes the stages involved in embryogenesis.

4. **Assessing the Relationship Between Assertion and Reason**:
- While both statements are true, the reason does not explain why the zygote is considered the first cell of a new generation.
- The assertion is about the zygote's role, while the reason discusses the process of embryogenesis, which is not directly related to the assertion.

5. **Conclusion**:
- Since both the assertion and reason are true, but the reason does not correctly explain the assertion, the correct choice is that both are true but the reason is not the correct explanation of the assertion.

### Final Answer:
- The correct option is: **Assertion true, Reason true, but Reason is not the correct explanation of Assertion.**

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