Farmer Brown decides that there is definitely a link between alfalfa and milk. He runs one more experiment, giving twenty of his cows 15 pounds of hay and 50 pounds of alfalfa. What prediction can you reasonably make about the outcome of this experiment?

Because the dependent variable has changed, predicting the outcome of the experiment is difficult.

Since the control is different, making an accurate prediction for this test is difficult. This is the best answer, because amount of hay, the control from the original experiment, has been altered. The dependent variable may change, but this is not the same as the control. In this case, it is the milk produced