You want to survey seventh-grade students about computer use. Which sample is more likely to be random? You ask seventh-graders entering a library on Friday night. You ask seventh-graders leaving a school basketball game. You ask seventh-graders leaving the cafeteria after lunch. You ask seventh-graders entering the computer lab.

You ask seventh-graders leaving the cafeteria after lunch.

Step-by-step explanation:

Try and choose a sample with the student group that has nothing to do with what you're testing for. It will take a bit of "creative" thinking and guessing about the lives of students in each of these groups. We try to choose a good sample to get accurate or less-biased results.

You ask seventh-graders entering a library on Friday night.

Friday night, some students are quicker to leave school and start the weekend. The students who go to the library might be more studious and work can be done on the computer. Libraries also have computers available for people to use for gaming. Your sample would have students who use the computer more.

You ask seventh-graders leaving a school basketball game.

Students who watch a basketball game usually do so by choice. We could assume that these students spend most of their free time playing sports, which are not done on the computer. Your sample would contain students who use a computer less.

You ask seventh-graders leaving the cafeteria after lunch.

The cafeteria is usually filled with all or most of the students in the entire school. Every student would need to eat, so you will find all "types" of students here. Your sample would contain all "types" of students.

You ask seventh-graders entering the computer lab.

These students very obviously use a computer, given you go to a place filled with computers to survey them. Your sample would mostly contain students who use a computer more.