A and are two alloys of gold and copper prepared by mixing metals in the ratio $$7 : 2$$ and $$7 : 11$$ respectively. If equal quantities of the alloys are melted to form a third alloy C, the ratio of gold and copper in C will be

A

$$5 : 7$$

B

$$5 : 9$$

C

$$7 : 5$$

D

$$9 : 5$$