A Consumer Research Firm Is Hired to Determine Which Brand

Multiple Choice

A consumer research firm is hired to determine which brand of laundry soap is most preferred by consumers. After surveying a sample of housewives, they find that the most preferred brand is White Suds. Which of the following is the greatest threat to external validity in this study?

A) Consumers' lack of interest in laundry products
B) The absence of difference in laundry soaps between manufacturers
C) The stereotypical assumption that only women do laundry
D) Including both males and females in research investigations