Bag I contains 4 white and 3 black marbles while bag II contains 3 white and 5 black marbles. One marble is drawn at random frombag I and put in bag II without seeing it. The probability that a marble drawnfrom bagII is a black one is

A

$$\frac{18}{63}$$

B

$$\frac{20}{63}$$

C

$$\frac{28}{63}$$

D

$$\frac{38}{63}$$