Which type of populations can have a smaller sample size?

The correct answer is that more homogeneous populations can indeed have a smaller sample size. This is due to the reduced variability within a homogeneous population, meaning that individuals in the population share more similar characteristics. When the members of a population are largely alike, the researcher can achieve a high degree of precision and reliability even with a smaller sample size. This is because the smaller sample will adequately represent the entire population's traits, leading to more accurate estimations of population parameters without the need for a larger sample.

In contrast, more diverse populations exhibit a greater range of characteristics and attributes among their members. As a result, larger sample sizes are typically required to capture the variation within the population effectively. Similarly, random populations don't have defined criteria for selection and can also be heterogeneous, requiring larger samples to ensure representativeness. More targeted populations might be focused on specific demographics or characteristics, but this does not inherently lead to a smaller necessary sample size, as the complexity of the characteristics may require a larger sample for adequate representation.