Answer:
The answer is choice A, a.k.a. (3,1)
Explanation:
It is given that triangle ABC is translated 2 units right and 5 units down to form triangle A′B′C′. It means triangle A'B'C' is translated 5 units right and 4 units up to form triangle A″B″C″.
Therefore the coordinates of vertex A″ are (3,1).