Which of the following best describes a sample?

A sample is best described as a subset of the population because it represents a portion of a larger group, allowing for analysis and insights without needing to examine the entire population. This method is essential in statistics and data analysis, as it makes research more feasible and cost-effective while still providing valuable information that can be generalized to the broader population. By selecting a sample, researchers can draw conclusions based on the behaviors, responses, or attributes of that smaller group, which ideally mirrors the characteristics of the entire population. This approach enables the analysis of trends and patterns while minimizing the time and resources required for data collection and processing.

Other options do not accurately capture the definition of a sample. For instance, a sample does not encompass every member of a population; that description would refer to a census. The claim that a sample is smaller than a target group is misleading since a target group can often constitute the entire population under study, and thus the sample may not necessarily be smaller. The assertion that a sample is irrelevant in data analysis overlooks its fundamental role in deriving insights and making informed decisions based on evidence rather than assumptions.