Given the triangles ABC and FHG
To check the similarity, find the ratio between the corresponding sides
Given AB = 72 and BC = 84 and AC = 48
And FH = 12 and HG = 14 and FG = 8
So,
The ratios will be as following:

As the ratio between the corresponding sides are equal to 1/6
So, the triangles are similar
So, the answer is option A.