A research group is on a college campus and is conducting a survey regarding the coffee consumption of college students in America. Which of the following techniques would probably produce a sample that is most representative of the population? Survey a randomly selected group of students that walk into the campus coffee shop.
Survey all students whose last name begins with R.
Survey a randomly selected group of students from an all-campus event.
Survey all students that attend their early morning class on a certain morning.

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