The average duration of human pregnancy is about nine months which is called:-

Options

A. Gestation period
B. Parturition
C. Lactation
D. Implantation

Answer

To solve the question, "The average duration of human pregnancy is about nine months which is called:", we need to identify the correct term that refers to this duration.

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking for the term that describes the average duration of human pregnancy, which is approximately nine months.

2. **Identify the Options**: The options given are:
- A) Gestation period
- B) Parturition
- C) Lactation
- D) Implantation

3. **Analyze Each Option**:
- **Gestation Period**: This term refers to the time from conception to birth, which in humans is approximately nine months or 36 to 38 weeks. This is the correct definition.
- **Parturition**: This term refers to the act of giving birth, not the duration of pregnancy.
- **Lactation**: This term refers to the period of breastfeeding after birth, which is also not related to the duration of pregnancy.
- **Implantation**: This is the process where the embryo attaches to the uterine wall, occurring shortly after fertilization, and does not refer to the duration of pregnancy.

4. **Select the Correct Answer**: Based on the analysis, the correct answer is **A) Gestation period**.

### Final Answer:
The average duration of human pregnancy is called the **gestation period**.

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