D. Angle Division
1) Examining that figure, we can take line segment QR and TS as parallel ones, and those line segments TN and NS as transversal ones.
2) In addition to this, since ∡QTS and ∡RST are right angles, then we have a rectangle. And since ∡NTS and ∡NST are congruent
3) Then we can say that NT bisects ∡QTS and NS bisects ∡RST
So, angle Division is the answer