Two simply supported beams are made up of the same material and are of the same cross section .Both beams carry uniformly distributed loads of equal intensities .one of the beam is 2 m long and the other is 4 m long . The 2 m long beam shows a central deflection of 1mm.what is the central deflection of the 4m long beam?

A

16 mm

B

2 mm

C

8 mm

D

1 mm