What Is the Advantage of a Double-Blind Experimental Design

Multiple Choice

What is the advantage of a double-blind experimental design?

A) The effects of extraneous variables are not eliminated but they are spread evenly across groups.
B) It makes the demand characteristics the same for participants in all conditions and eliminates the possibility that the experimenter unintentionally signals the expected outcome to the participants.
C) It increases confidence that the data are being interpreted in an unbiased manner.
D) It makes it impossible for the participant to discover the hypothesis and assures that the data are interpreted in terms of what actually happened, not in terms of what "should" have happened.