Relationship between modulus of elasticity E, modulus of rigidity G and Poisson’s ratio $$\mu$$ is

A

$$G = \frac {E}{2(1 + \mu)}$$

B

$$G = E(2 - \mu)$$

C

$$E = G (1 + \mu)$$

D

$$G = \frac {E}{1 + \mu}$$