Geometry

Question Analysis
This question involves the concept of population in statistics.
The main focus is to distinguish between a population (entire group of interest) and a sample (subset of the population).

Key Concept Explanation
Population: The complete set of individuals, items, or events being studied.
Sample: A subset of the population used to make inferences about the whole.

Step-by-Step Solution
Identify the research goal: "average study time of high school students."
Evaluate the options:
A, D: Represent samples (subset of students).
B: "All high school students worldwide" is the entire population of interest...