Gestation period of 280 days is calculated from time of

Options

A. Lasat menstruation
B. Fertilization
C. Next menstruation
D. Puberty.

Answer

To solve the question regarding the gestation period of 280 days, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Gestation Period**:
- The gestation period refers to the time from conception until the birth of the child. It is the duration of pregnancy.

2. **Identify the Standard Duration**:
- The typical duration of a human gestation period is approximately 280 days, which is equivalent to about 40 weeks.

3. **Determine the Starting Point for Calculation**:
- The gestation period is commonly calculated from a specific point in the menstrual cycle.

4. **Review the Options Provided**:
- The options given are:
a. Last menstruation
b. Fertilization
c. Next menstruation
d. Puberty

5. **Analyze Each Option**:
- **Option A (Last menstruation)**: This is the standard method for calculating the gestation period. It starts from the first day of the last menstrual period (LMP).
- **Option B (Fertilization)**: While fertilization is when conception occurs, it is not the standard reference point for calculating the gestation period.
- **Option C (Next menstruation)**: This option does not apply as the gestation period is not calculated from the next menstruation.
- **Option D (Puberty)**: This is irrelevant to the calculation of the gestation period.

6. **Conclude the Correct Answer**:
- Based on the analysis, the correct answer is **Option A: Last menstruation**. The gestation period of 280 days is calculated from the first day of the last menstrual period.

### Final Answer:
**The gestation period of 280 days is calculated from the time of the last menstruation (Option A).**

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