The answer would be 11/20.
0.55 is the same as 55/100 (55/100)
Find the GCF of both 55 and 100 and that would be 5 since 5 * 11 = 55 and 5 * 20 = 100
Divide 55 and 100 both INDIVIDUALLY by 5 and u get 11/20.
It is the third option.
If you need any explanation, I can edit this later.
Good luck!!