A researcher conducted a survey to determine whether people in a certain large town prefer watching sports on television to attending the sporting event. The researcher asked 117 people who visited a local restaurant on Saturday, and 7 people refuse to respond. Which of the following factors makes it least likely that a reliable conclusion can be drawn about the sports-watching preferences of all people in the town?
A) Sample size
B) Population size
C) The number of people who refused to respond
D) Where the survey was given