In Comparison with Purely Between-Subjects Experimental Designs,one Drawback of Purely

Multiple Choice

In comparison with purely between-subjects experimental designs,one drawback of purely within-subjects experimental designs is that:

A) they usually do not do as good a job of controlling for individual differences
B) they require the use of matching,which is very difficult to perform effectively
C) they open the door to problems such as sequence effects or carryover effects
D) they are usually more costly and time-consuming than between-subjects designs