In the Context of Demography, Which of the Following Best

In the context of demography, which of the following best defines a population?

A) A group of people who share similar cultural values and are scattered around the world
B) A group of people who are immigrants from different countries
C) A group of people who live in similar climatic conditions across the world
D) A group of people who share a geographic territory
E) A group of people who belong to a particular age group