Hank is running for re-election as mayor. He wants to find out if he has a good chance of being elected, however, since there are 1,500 people in his town, he doesn't have time to ask each person in town who they are voting for. He decides to take a random sample instead. Which of the following strategies would help Hank ensure a random sample? A. He could go door to door and ask 30 various people in his neighborhood. B. He could send an email to 30 city workers. C. He could ask 30 people as they enter church on Sunday. D. He could use a computer to pick 30 random addresses of people that live in the town.