Which of the following statements are incorrect
I. A rapid decline in the death rate is the only reason for the population explosion.
II. The marriageable age decided by the government is 18 years for females and 21, years for males.
III. An ideal contraceptive is the one that reduced the sexual drive of the user .
IV. The ' one child norm has mostly been adopted by people living in rural areas.

Options

A. I, II and III
B. I,III and IV
C. I and II
D. III and IV

Answer

To determine which of the statements are incorrect, let's analyze each statement one by one.

### Step 1: Analyze Statement I
**Statement I:** A rapid decline in the death rate is the only reason for the population explosion.

- **Analysis:** This statement is incorrect. While a decline in the death rate contributes to population growth, the primary factor for a population explosion is often an increase in the birth rate. Thus, this statement is misleading as it suggests that the decline in death rate is the sole reason.

### Step 2: Analyze Statement II
**Statement II:** The marriageable age decided by the government is 18 years for females and 21 years for males.

- **Analysis:** This statement is correct. The legal marriageable age in many countries, including India, is indeed set at 18 years for females and 21 years for males. This regulation aims to control population growth by delaying the age of marriage and consequently the age of childbirth.

### Step 3: Analyze Statement III
**Statement III:** An ideal contraceptive is the one that reduces the sexual drive of the user.

- **Analysis:** This statement is incorrect. An ideal contraceptive should not interfere with the sexual drive or libido of the user. Instead, it should effectively prevent pregnancy without affecting the user's sexual experience. Therefore, this statement is misleading.

### Step 4: Analyze Statement IV
**Statement IV:** The 'one child norm' has mostly been adopted by people living in rural areas.

- **Analysis:** This statement is also incorrect. The 'one child norm' has primarily been adopted by urban populations due to various socio-economic factors. Rural areas tend to have different cultural and social dynamics that often lead to larger family sizes. Thus, this statement is misleading.

### Conclusion
Based on the analysis:
- **Incorrect Statements:** I, III, and IV
- **Correct Statement:** II

### Final Answer
The incorrect statements are I, III, and IV.

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