A solid shaft of diameter D carries a twisting moment that develop maximum shear stress. If the shaft is replaced by a hollow one of OD = D and ID = $$\frac{3}{4}$$ D; then the maximum shear stress will be

A

$$\frac{16}{15} \tau $$

B

$$\frac{15}{16} \tau $$

C

$$\frac{256}{175} \tau $$

D

$$\frac{175}{256} \tau $$