The compound ratio of 5:6, 3:2 and 4:5?  Choose the correct answer.
A) 1 : 8  B) 1 : 6  C) 1 : 2  D) 1 : 1  E) 1 : 7

Rationale: "5 / 6 * 3 / 2 * 4 / 5 = 1 / 1 1 : 1 answer : d"
Answer: D