The question says, 12 yards to 20 feet. First let's convert the units. One yard is equal to 3 feet. So if we multiply,

. Now we will, divide 36 feet to 20 feet and we'll simplify.

both 36 and 20 are divisible by 4, that means 4 is their common factor. We can simplify by that.
The answer is D. 9:5