A researcher randomly chooses eight sections of a course and collects data from students in each section for a study. What sampling technique is this?

• A. Simple random sampling
• B. Stratified sampling
• C. Cluster sampling
• D. Systematic sampling

Answer: (C)

Cluster sampling is being used here. The researcher randomly selects whole groups and then collects data from every member within those groups. In this case, eight sections of a course are natural groups (clusters), and data are gathered from all students in the chosen sections.

This differs from simple random sampling, where individual students are chosen from the entire population, giving each student an equal chance to be included. It also differs from stratified sampling, which would involve dividing students into strata (like by major or year) and sampling from within each stratum, not by whole sections. Systematic sampling would involve selecting every nth student from a list. Cluster sampling is often chosen for practicality when groups are easy to sample and data can be collected from all members of the selected groups, though it can reduce precision if the clusters are not homogeneous.