Wagner Machine Tool Produces Output According to Q = 4(KL)^1/2,where

Wagner Machine Tool produces output according to Q = 4(KL) ^1/2,where K is the amount of capital used and L is the amount of labor employed.Capital costs $2 per unit,and Wagner is constrained in the short run to use 16 units of capital.If labor costs $8 per unit,Wagner's minimized short-run marginal cost at an output of 48 is:

A) $3.00.
B) $3.50.
C) $4.00.
D) $4.50.
E) $5.00.