The belief that the mother is completely responsible for the sex of the child is wrong because the child

Options

A. gets sex chromosome only from the mother.
B. develops in the body of the mother
C. gets one sex chromosome from the mother and the other from the father
D. gets sex determining chromosome only from the father.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that the belief that the mother is solely responsible for the sex of the child is incorrect. We need to explore why this belief is wrong.

2. **Identifying the Chromosomes**:
- Males have two types of sex chromosomes: X and Y.
- Females have two X chromosomes (XX).
- Therefore, the male gametes (sperm) can carry either an X or a Y chromosome, while the female gametes (eggs) always carry an X chromosome.

3. **Determining the Child's Sex**:
- The sex of the child is determined by the combination of sex chromosomes from both parents.
- If the sperm carrying an X chromosome fertilizes the egg (which also carries an X chromosome), the resulting child will be female (XX).
- If the sperm carrying a Y chromosome fertilizes the egg, the resulting child will be male (XY).

4. **Conclusion**:
- The sex of the child is not determined solely by the mother but rather by the combination of chromosomes contributed by both parents. The father contributes either an X or a Y chromosome, which ultimately determines the sex of the child.

5. **Final Statement**: Thus, the belief that the mother is completely responsible for the sex of the child is incorrect because the father contributes either an X or a Y chromosome, which is crucial for determining the child's sex.