Answer: A)
Explanation:
OK so if a figure is a dilation of another figure that means that is has the same angles but the sides are going to be smaller or bigger. Even though the sides are a different size they are proportional. So if I divided the length of AB over XY I'd get 5 since that is the scale factor. If I did that with AC over XZ I'd get 5 again because that is the scale factor. That's because they were proportional. Let's say this wasn't a dilation and AB over XY was 5 but AC over XZ was 4 that would mean it isn't proportional because AB would be 5 times bigger but XZ is only 4 times bigger.