Hello, and thank you for posting your questions here on brainly.
To find this, all we have to do is simplify 30:45 to its lowest terms.
The GCD (greatest common divisible) is 15. Now, we divide 30 and 45 by 15.
30 / 15 = 2
45 / 15 = 3
Which gives us the ratio 2:3.
According to this, the answer is B. 2.
Hope this helps! ☺♥