Final answer:
The correct answer is C.) The surveyed residents are the sample, as they are a subset of the overall population of city residents which the survey aims to understand regarding weekly earnings.
Step-by-step explanation:
In research methodology within the context of statistics, the term population refers to the entire group of individuals or instances that researchers are interested in studying, whereas a sample is a subset of the population that is actually observed or analyzed in order to make inferences about the population. When a researcher is interested in researching weekly earnings in large cities across the country and conducts a survey among 100 residents in a city to determine their weekly earnings, the residents in the city are considered the population as they represent the entire group that is of interest. On the other hand, the surveyed residents, those 100 individuals who actually took part in the survey, represent a sample.
The correct option is C.) The surveyed residents are the sample. This is because they are a smaller group selected from the larger group, which is the entire pool of residents in the city, to participate in the study. This allows the researcher to make inferences about the population of city residents based on the findings from this sample.