You Have Been Asked to Help a Top Nutrition Researcher

You have been asked to help a top nutrition researcher conduct human experiments on vitamin C.As the subjects walk into the laboratory,you distribute all the vitamin C pill bottles to the girls and all the placebo pill bottles to the boys.The researcher instantly informs you that there are two errors in your research practice.What steps should you have done differently?

A) Given all the boys the vitamin C and the girls the placebo,and told them what they were getting
B) Distributed the bottles randomly,randomized the subjects,and told them what they were getting
C) Told the subjects which group they were in,and prevented yourself from knowing the contents of the pill bottles
D) Prevented yourself from knowing what was in the pill bottles,and distributed the bottles randomly to the subjects