Which of the following Is correct?

Options

A. Clitoris of female and glans penis of the male are homologous organs
B. The ration of number of gametes produced by spermatogenesis to the number of gametes produced by oogenesis is `4:1`
C. Trophoblast cells lying over the embryonic disc are cells of Rauber
D. All of the above

Answer

To determine which of the statements provided in the question is correct, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Analyze Option 1: Clitoris of female and glans penis of male are homologous organs.**
- The clitoris is a small, sensitive organ located at the top of the vulva in females, while the glans penis is the sensitive tip of the penis in males. Both structures develop from the same embryonic tissue and serve similar functions related to sexual arousal. Therefore, this statement is correct.

2. **Analyze Option 2: The ratio of the number of gametes produced by spermatogenesis to the number of gametes produced by oogenesis is 4:1.**
- Spermatogenesis is the process of sperm production in males, resulting in four viable sperm cells from one precursor cell. In contrast, oogenesis in females typically produces one viable egg and three polar bodies (which are not functional gametes). Thus, the ratio of sperm to egg produced is indeed 4:1. This statement is also correct.

3. **Analyze Option 3: Trophoblast cells line over the embryonic disc cells of the blastocyst.**
- The trophoblast is the outer layer of cells in the blastocyst that eventually helps in implantation and forms part of the placenta. The embryonic disc is formed from the inner cell mass of the blastocyst. The trophoblast cells do indeed line over the embryonic disc cells. Therefore, this statement is correct as well.

4. **Conclusion: All statements are correct.**
- Since all three options have been verified as correct, the final answer is that option 4, which states "all of the above," is the correct answer.

### Final Answer:
**Option 4: All of the above.**

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