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Why is it essential to eliminate or control for extraneous factors when conducing a research experiment? A) Management has little patience for research results that aren't tightly focused. B) Additional factors inevitably raise research costs. C) If you can't eliminate or control them, you can't be sure that the results you see were related to the variables you were trying to test. D) Extraneous factors can make experiments run past schedule. E) Test subjects don't want to be asked about extraneous factors