Which of the following type of age pyramid reflects a stable population growth ?

Options

A. Triangular
B. Bell-shaped
C. Urn-shaped
D. Both bell-shaped and urn-shaped.

Answer

To determine which type of age pyramid reflects stable population growth, we need to analyze the characteristics of different age pyramids. Here’s the step-by-step solution:

### Step 1: Understand the Types of Age Pyramids
There are three main types of age pyramids:
1. **Triangular Pyramid**: This shape indicates a high birth rate with a larger number of individuals in the younger age groups. It reflects an expanding population.
2. **Bell-Shaped Pyramid**: This shape indicates a balanced distribution of age groups, where the number of individuals in pre-reproductive, reproductive, and post-reproductive phases are relatively equal. It reflects a stable population.
3. **Inverted Pyramid (or Un-Shaped)**: This shape indicates a higher number of older individuals compared to younger ones, suggesting a declining population.

### Step 2: Identify the Stable Population Growth
From the descriptions:
- The **triangular pyramid** indicates an expanding population due to a larger number of young individuals.
- The **bell-shaped pyramid** indicates stability, as it shows a balanced number of individuals across all age groups.
- The **inverted pyramid** indicates a declining population due to a larger number of older individuals.

### Step 3: Conclusion
The age pyramid that reflects stable population growth is the **bell-shaped pyramid**. This is because it shows a balance between the pre-reproductive, reproductive, and post-reproductive phases.

### Final Answer
The correct answer is **bell-shaped pyramid**.

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