A new shampoo claims to significantly increase hair growth. To test this, researchers conduct an experiment in which subject A uses the shampoo once a day for 30 days but subject B does not. After 30 days, subject A has had significant hair growth compared to subject B. Should the results of this experiment be used to support the product claims?

a. No. The experiment does not include enough subjects in each group.

b. Yes. The experimental design is sound.

c. No. The experiment does not include a control group.

d. Yes. The results support that the shampoo does what it claims.

e. No. The results do not support that the product does what it claims.