Which two ratios form a proportion?

Question

Responses
A 12/15
and 5/4
12 /15 and 5/ 4
B 6/5
and 4/5
6 /5 and 4/ 5
C 15/12
and 5/4
15 /12 and 5/ 4
D 5/6
and 4/5

Answer 1

5 /6 and 4/ 5