Imlantation is delayed for several days in

Options

A. Human beings
B. Seals
C. Bats
D. Both B and C

Answer

**Step-by-Step Solution:**

1. **Understanding Implantation**: Implantation is the process by which a fertilized egg (embryo) attaches itself to the lining of the uterus. This is a crucial step in the development of a pregnancy.

2. **Identifying the Organisms**: The question asks about which organisms experience delayed implantation. The options given are:
- A. Human beings
- B. Seals
- C. Bats
- D. Both B and C

3. **Analyzing Each Option**:
- **Human beings**: In humans, implantation occurs about 6 to 10 days after fertilization, so it is not delayed.
- **Seals**: Seals are known to have a delayed implantation period that can last from 4 to 6 months.
- **Bats**: Bats also exhibit delayed implantation, allowing them to time the birth of their young to favorable environmental conditions.
- **Both B and C**: This option suggests that both seals and bats experience delayed implantation.

4. **Conclusion**: Since both seals and bats are known to have delayed implantation, the correct answer is D. Both B and C.

**Final Answer**: D. Both B and C (Seals and Bats)

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