Ratio of Copper and Gold in first and second alloy are 3 : 4 and 2 : 5 respectively. 14 kg of the first alloy is mixed with 21 kg of the second alloy. Find the ratio of Copper and Gold, respectively, in the new mixture.

A

17 : 13

B

12 : 23

C

5 : 9

D

23 : 12