A,B, C and D are four positive numbers such that A is $$\frac{3}{4}$$ times of B, B is $$\frac{4}{5}$$ times of C, and C is $$\frac{3}{8}$$ times of D. If the average of 4 times of A and 7 times of D is 316, then the average of all the four numbers A, B, C and D is:

A

36

B

38

C

28

D

34