Control group experiment versus the variable......?

I have two groups of tadpoles.


I give Group A Thyroxin, a hormone that frogs already create. But i don't give any to Group B.


After a while, I see Group A (with the Throxin) grow faster than group B.





QUESTION: Which group is the control group and which is the variable?





Remember Group A has the extra hormone and group B doesnt.Control group experiment versus the variable......?
Group B will be your control group because you are ';controlling'; the group by not giving them any hormone.

beauty