The knife, because its a knife
Answer:
Dr. Reside's experiment can not be considered effective because his study has only treatment subjects group and lack of control group. That's why his study can be very good but not valid without control group.
In his study, he concluded that 80% children after therapeutic treatment decreased the activity level which can be true but not valid without control group because when he use control group in his study then we will be able to compare the normal or control group and treatment group. Then the study will be valid and effective as well.
B is nota component of rhis
