The Proportional Medians Theorem states:If two triangles are similar, then the ratio of the lengths of two corresponding medians is the same as the ratio of the lengths of two corresponding sides.
A median of a triangle is a line segment joining a vertex to the midpoint of the opposing side, bisecting it.
It is given the two triangles are similar.FG and TU are the medians of the triangle .
By Proportional Medians Theorem ratio of the lengths of two corresponding medians is the same as the ratio of the lengths of two corresponding sides.
So

Option D. Proportional Medians Theorem is the right answer.