The birth and death rates of four countries are given below. Which one will have the least population growth rate ?
`{:("Country","Birth rate"//1000,"Death rate"//1000),(P,15,5),(Q,25,10),(R,35,18),(S,48,41):}`

Options

A. P
B. Q
C. R
D. S

Explanation

To determine which country has the least population growth rate based on the given birth and death rates, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Formula for Population Growth Rate**:
The population growth rate can be calculated using the formula:
\[ \text{Population Growth Rate} = \text{Birth Rate} - \text{Death Rate} \]

2. **Identify the Birth and Death Rates for Each Country**:
- For Country P:
- Birth Rate = 15/1000
- Death Rate = 5/1000
- For Country Q:
- Birth Rate = 25/1000
- Death Rate = 10/1000
- For Country R:
- Birth Rate = 35/1000
- Death Rate = 18/1000
- For Country S:
- Birth Rate = 48/1000
- Death Rate = 41/1000

3. **Calculate the Population Growth Rate for Each Country**:
- For Country P:
\[ \text{Growth Rate} = 15 - 5 = 10 \text{ (per 1000)} \]
- For Country Q:
\[ \text{Growth Rate} = 25 - 10 = 15 \text{ (per 1000)} \]
- For Country R:
\[ \text{Growth Rate} = 35 - 18 = 17 \text{ (per 1000)} \]
- For Country S:
\[ \text{Growth Rate} = 48 - 41 = 7 \text{ (per 1000)} \]

4. **Compare the Growth Rates**:
- Country P: 10
- Country Q: 15
- Country R: 17
- Country S: 7

5. **Identify the Country with the Least Population Growth Rate**:
From the calculated growth rates, Country S has the lowest growth rate of 7 per 1000.

### Final Answer:
The country with the least population growth rate is **Country S**.

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