What the question is referring her by magnitude is units away from 0. 3.7 is 3.7 units away from 0, which is the same thing as the absolute value of 3.7. And since absolute value is always positive, C is already out. D is also out as the value doesn't change. B's reason contradicts the answer, so it is also wrong. This leaves A (3.7, because |3.7| = 3.7) as our answer.
