Steel wire has a length of 2m and a cross-sectional area of 1mm². When 20 N force is applied to the wire its length is increased by 2 x 10^-4m. What is Young's modulus for steel?

A 2.5 x 10¹¹ N-m^-2

B 2.25x 10¹¹ N-m^-2

C 3.5x 10¹¹ N-m^-2