Sex ratio is the

Options

A. ratio of females to males
B. ratio of males to females
C. both 1 and 2
D. ratio of infant girl to infant body

Answer

To answer the question "Sex ratio is the", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Definition**: The sex ratio is a demographic measure that indicates the proportion of males to females in a population.

2. **Analyzing the Options**:
- **Option 1**: Ratio of females to males - This is incorrect as it does not represent the standard definition of sex ratio.
- **Option 2**: Ratio of males to females - This aligns with the standard definition of sex ratio.
- **Option 3**: Both 1 and 2 - This is incorrect since only option 2 is correct.
- **Option 4**: Ratio of infant girls to infant boys - This is a specific case and does not represent the general definition of sex ratio.

3. **Conclusion**: Based on the analysis, the correct answer is **Option 2**: Ratio of males to females.

### Final Answer:
Sex ratio is the ratio of males to females (Option 2).

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