The student body president takes a random sample of everyone who attends the Friday night football game and gathers opinions about the upcoming school dance. The sample that results is ______.
A. representative since only students will attend the Friday night football game
B. biased because not every student attends the Friday night football game
C. unbiased since the student body president conducted a random sample
D. systematic since the student body president had a system in place to create the sample