A transversal t meets three distinct lines p, q and r at points P, Q and R respectively. On the left side of t and above each line, the angles formed are 68∘ at P, 112∘ at Q and 68∘ at R. Which pair of lines must be parallel?
a) p∥q
b) q∥r
c) p∥r
d) No two of the lines are parallel