An age pyramid illustrates

Options

A. Different trophic levels in a community
B. Population density
C. Percentage of persons in successive age categories in a given population
D. Population natality rate

Answer

To answer the question "An age pyramid illustrates," we need to analyze the options provided and understand what an age pyramid represents.

### Step-by-Step Solution:

1. **Understand the Concept of an Age Pyramid**:
- An age pyramid, also known as an age-sex pyramid, is a graphical representation that shows the distribution of various age groups in a population. It typically has two back-to-back bar graphs, one for males and one for females.

2. **Identify the Purpose of an Age Pyramid**:
- The primary purpose of an age pyramid is to illustrate the demographic structure of a population. It provides insights into the age distribution and sex ratio, which are crucial for understanding population dynamics.

3. **Analyze the Options Given**:
- The options provided are:
a) Different trophic levels in a community
b) Population density
c) Percentage of persons in successive age categories in a given population
d) Population natality rate

4. **Eliminate Incorrect Options**:
- Option (a) refers to ecological pyramids, which are not related to age distribution.
- Option (b) refers to population density, which does not specifically relate to age or sex.
- Option (d) refers to natality rate, which is about birth rates and not age distribution.

5. **Select the Correct Option**:
- Option (c) states "percentage of persons in successive age categories in a given population." This directly relates to what an age pyramid illustrates, as it shows the proportion of individuals in different age groups.

6. **Conclusion**:
- Therefore, the correct answer is option (c): "percentage of persons in a successive age category in a given population."

### Final Answer:
An age pyramid illustrates the percentage of persons in a successive age category in a given population.

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