Choose the incorrect match.

Options

A. First month : formation of heart begins.
B. Second month : development of limbs and digits
C. Third month : most of the major organ systems are formed .
D. Sixth month : first movements of the fetus is sensed

Answer

To solve the question of identifying the incorrect match regarding fetal development stages, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Option 1: Heart Formation in the First Month**
- In the first month of pregnancy, the heart begins to form and starts beating around 18 days after conception. By the end of the first month, the embryo is about 1/10th of an inch in size.
- **Conclusion**: This option is correct.

2. **Option 2: Limb and Digit Development in the Second Month**
- By the end of the second month, the fetus is about the size of a kidney bean. During this month, limb buds develop into arms and legs, and distinct webbed fingers begin to form.
- **Conclusion**: This option is also correct.

3. **Option 3: Development in the Third Month**
- By the end of the third month, the fetus measures about 2 to 3 inches in length. The fetus can swallow and kick, and all major organs and muscles are formed by this time.
- **Conclusion**: This option is correct as well.

4. **Option 4: First Movement and Sensation in the Sixth Month**
- The question states that the first movement is the sense of the fetus. However, the first movements (quickening) are typically felt around the second month, not the sixth month. By the sixth month, the fetus can hear sounds and has visible eyebrows and eyelids, but the statement regarding the first movement being a sense is incorrect.
- **Conclusion**: This option is incorrect.

### Final Answer:
The incorrect match is **Option 4**.

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