Which of these is the name for human embryonic development?

Options

A. a placenta
B. a contraction
C. a blastocyst
D. Gestation period

Answer

### Step-by-Step Solution:

1. **Understanding Human Embryonic Development**: Human embryonic development refers to the process that occurs from fertilization until the birth of the baby. This development takes place in the mother's womb.

2. **Identifying the Duration**: The entire process of human embryonic development lasts approximately 9 months, which is crucial for the growth and maturation of the embryo into a fetus.

3. **Terminology**: The specific term used to describe this 9-month period of development is known as the "gestation period."

4. **Conclusion**: Therefore, the correct answer to the question "Which of these is the name for human embryonic development?" is the "gestation period."

### Final Answer:
The name for human embryonic development is the **gestation period**.

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