Final answer:
The correct term for a complete list of individuals eligible to be included in a sample is 'sampling frame'. It is essential for the validity of a study's results and ensures an unbiased representation of the population.
Step-by-step explanation:
The complete list of individuals in the population eligible to be included in the sample is called the sampling frame. When conducting research, regardless of whether it's with a large population or a smaller sample group, having an accurate sampling frame is crucial. It ensures that every individual has an equal opportunity to be selected for the study, which is essential for the validity of the research findings. Choosing a random sample is an effective way to select participants because it ensures that everyone has the same chance of being part of the study. This method avoids bias that could influence the results and thereby provides a fair representation of the population. If the sampling frame were to be drawn from sources like magazine subscription lists, it might not be representative of the general population, leading to biased results due to under-representation of certain groups.