In the diagram, points R and S lie on P T and P Q, respectively. If \angle P Q R=90^{\circ}, \angle Q R T=158^{\circ}, and \angle P R S=\angle Q R S, what is the measure of \angle Q S R ?
Answer Choices
A. 34^{\circ}
B. 22^{\circ}
C. 68^{\circ}
D. 11^{\circ}
E. 79^{\circ}