An instructor teaching an introductory course in marketing has 300 students enrolled in her class. Some students in the class request the instructor to cancel her class on Wednesday before Thanksgiving. She agrees to do so if 70 percent of the students agreed with the proposal to cancel the class. Instead of asking every student to participate in the poll, she asks students to write their names on index cards and put them in a collection basket. She then asks a student to pull out 30 cards from the basket without looking at the basket or the cards. The instructor is practicing what kind of sampling technique?

a. Systematic random sample
b. Simple random sample
c. Stratified random sample
d. Convenience sample
e. Judgment sample

Ans: b. Simple random sample