Answer:
C, the biggest triangle with its vertices at (0,5) and (10,0).
Step-by-step explanation:
I will refer to the 2nd image's triangle as A, the 3rd as B, and the 4th as C.
First, let's look at the original triangle. Two of its vertices are at (0,3) and (6,0).
Now, let's look at A. Two of its vertices are at (0,3) and (9,0). One of the vertices is in the same location, aka (0,3), as the original triangle. A proper dilation would have increased the lengths of all sides of the triangle, so this can't be the right answer.
B is obviously much smaller than the original triangle, so we can take one look at it and know that it is not the correct answer because the problem specifies that the original triangle was dilated by a scale factor GREATER than 1, aka the dilated triangle would have to be bigger than the original. So, this is wrong, too.
This leaves us with C. It is dilated to a size bigger than the original, and each side length was dilated, so I think it is safe to assume that this is the correct answer.
Hopefully this helped, and if I was correct, I'd appreciate it if you marked me as the Brainliest :)