Tamara is writing statements to prove that the sum of the measures of interior angles of triangle PQR is equal to 180°. Line M is parallel to line N. Line n is parallel to line M. Triangle QPR has vertex P on line N and vertices Q and R on line M. Angle QOR is 135. Which is a true statement she could write?
A. Angle PRQ measures 30°.
B. Angle PRQ measures 15°.
C. Angle PQR measures 15°.
D. Angle PQR measures 45°.