A __________ includes all the subgroups within a given population in numbers that are proportionally equal to those found in that population.

A) selective sample
B) survey group
C) biased sample
D) representative sample

A representative sample accurately reflects the diversity within a given population, ensuring that no one subgroup is overrepresented or underrepresented. This is important for obtaining reliable and generalizable results. A selective sample intentionally targets a specific subgroup, a survey group is simply the group of individuals who responded to a particular survey, and a biased sample is one that systematically overrepresents or underrepresents certain subgroups, potentially leading to inaccurate results.