75 POINTSSSSSS!!!!!!!!!
 Which of these is an example of a random sample? 
 A. 
 A phone plan company surveys people on the beach to see how well they are receiving service, and uses this information in future advertising.
 B. 
 Customers buying a new cell phone are surveyed about cell phone plans.
 C. 
 Every twentieth caller to an independent radio station receives tickets to a concert.
 D. 
 A phone survey is conducted using twenty names randomly taken from the phone book.