You are presented with the quiz "If the rate of breathing is too fast or too slow, what my become unstable?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "blood pH may become unbalanced if the rate of breathing is too fast or too slow" and "when a compound is unbalanced it becomes unbalanced and unstable". 

So, what's the best answer to the question?


 

      blood pH     