In the opposite figure, the graph (1) represents the output voltage generated from the AC dynamo while the graph (2) represents the output voltage which generated from the same AC dynamo after making some modifications to it that can be \( \qquad \)
(A) Decreased the area of the coil to half.
(B) Increased the area of the coil to double.
(C) Doubled the number of turns of the coil.
(D) Doubled the angular velocity of the coil.