In a group of ducks and cows, the total number of legs are 34 more than twice the no. of heads. Find the total no.of buffaloes.  Select:  A) 11  B) 12  C) 14  D) 17  E) 18

Rationale: "let the number of buffaloes be x and the number of ducks be y = > 4 x + 2 y = 2 ( x + y ) + 34 = > 2 x = 34 = > x = 17 d"
Answer: D