You Want to Test People's Cola Preferences

Multiple Choice

You want to test people's cola preferences.So,you conduct a taste test using two different brands of cola.However,you are worried about possible clues you may give people taking the
Test.So,you label the two colas and have your assistant,who does not know which cola is
Which,to administer the test to the subjects.Thus,you have prevented yourself and your
Assistant from giving out any clues by using

A) random selection.
B) random assignment.
C) a single-blind experiment.
D) a double-blind experiment.