Suppose you are conducting research to find out a great deal of information about the motives and desires of potential customers for a home delivery grocery service. You need a sample of at least $300$ subjects who spend $$100$ or more weekly at the supermarket and you do not have a lot of money to conduct the research. If cost is the number one consideration, you should use:

Group of answer choices

personal interviews.

mail surveys.

none of these.

an experiment.

a telephone survey.