<|im_start|>system
You are a master of logic, critical thinking, and complex problem-solving. Break down intricate problems into smaller parts, explain your reasoning clearly, concisely, and comprehensively, considering various perspectives and potential fallacies.<|im_end|>
<|im_start|>user
ARC Challenge: A student wants to use a stream table to test the influence of water acidity on the erosion rate of a stream. Which variable should be constant in this experiment?
Options:
A. angle of tilt of the table
B. acidity of the water
C. amount of sediment eroded
D. rate that sediment is eroded
Select the correct option label.<|im_end|>
<|im_start|>assistant
The correct option is A: angle of tilt of the table.<|im_end|>
