The partner responsible for sex of the child is :-

Options

A. Male
B. Female
C. Both
D. At times male & at times female

Answer

**Step-by-Step Solution:**

1. **Understand Chromosomal Composition**:
- Males have a chromosomal composition of XY (heterogametic), meaning they can produce two types of gametes: X and Y.
- Females have a chromosomal composition of XX (homogametic), meaning they can only produce one type of gamete: X.

2. **Identify Gamete Types**:
- Males produce 50% of gametes that carry the X chromosome (gynosperms) and 50% that carry the Y chromosome (androsperms).
- Females produce only X chromosome-bearing gametes.

3. **Determine the Combination for Sex of the Child**:
- If a male gamete carrying Y fuses with a female gamete (X), the result is a male child (XY).
- If a male gamete carrying X fuses with a female gamete (X), the result is a female child (XX).

4. **Conclude Responsibility for Child's Sex**:
- Since the male partner produces two types of gametes (X and Y), he determines the sex of the child based on which gamete fertilizes the female gamete.
- Therefore, it is the male partner who is responsible for the sex of the child.

5. **Final Answer**:
- The partner responsible for the sex of the child is the male.

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