A uniform wire (Young's modulus 2 x 10 Nm-2) is subjected to longitudinal tensile stress of 5x 107Nm 2. If the overall volume change in the wire is 0.02%, the fractional decrease in the radius of the wire is close to (A) 1.0 10-4 (B) 1.5 x 10-4 (C) 0.25 10 (D) 5 x 10-4