Answer:
The answer is A.
Explanation:
The first triangle is shown to be the original before the reduction version. The first triangle would be original height/ original base, since we know it is the original because it is shown in front of the reduction version. The reduction version is the small triangle to the right, and it is smaller than the original triangle, making it reduction height, since it is the reducted version of the original height, divided by the reduction base. Your answer would be A.