If ∆QRS≅∆TUV, then their corresponding sides would be equal.
so, QS = TV
7v - 9 = 4v + 3
7v - 4v = 3 + 9
3v = 12
v = 12/3
v = 4
Then, QS = 4(4) + 3 = 16 + 3 = 19
& Also, TV = 7(4) - 9 = 28 - 9 = 19
In short, Your Answer would be Option C
Hope this helps!