Which graph represents the age and sex of a population?

• A. A line graph
• B. A population pyramid
• C. A bar chart of GDP
• D. A heat map

Answer: (B)

This is about recognizing the chart that shows how many people live in each age group and how many are male or female. A population pyramid is designed specifically for that purpose. It typically lists age groups along one axis and uses horizontal bars to show the number (or share) of people in each group, split into two sides for males and females. This dual-sided, age-structured view lets you see the overall shape of the population, such as a broad base with many young people (high birth rates) or an aging pattern if the upper ages are comparatively larger.

The other graphs aren’t built for this kind of demographic breakdown: a line graph tracks changes over time for a single variable, a bar chart of GDP shows economic output, and a heat map displays intensity across a grid for different values.