Vessels A and B contain solutions of acid and water. The ratio of acid and water in vessel A is 7 : 5 and that in vessel B is 11 : 13. Four litres of solution from vessel A is mixed with 5 litres of solution from vessel B. What is the ratio of acid and water in the mixture?

A

35 : 37

B

22 : 21

C

37 : 35

D

21 : 22