A simple random sample of 1000 American adults found that the average number of hours spent watching television during a typical week was 13.8. A simple random sample of 500 Canadians yielded an average of 12.5 hours per week of television viewing. Assume that for the American and Canadian distributions for weekly television, viewing times have the same standard deviations. The sampling variability associated with these sample means is:

a. smaller for the sample of Canadians, because the population of Canada is less than half that of the United States.
b. larger for the sample of Canadians, because Canadian citizens are more widely dispersed throughout their country than American citizens are in the United States. Hence, Canadians have more variable views.
c. smaller for the sample of Canadians, because their population is smaller.
d. larger for the sample of Canadians, because the sample size is smaller.