Find the measure of ∠1. Justify your answer.
A.
m∠1 = 60 because corresponding angles of parallel lines are supplementary.
B.
m∠1 = 120 because corresponding angles of parallel lines are congruent.
C.
m∠1 = 120 because same-side interior angles of parallel lines are congruent.
D.
m∠1 = 60 because same-side interior angles of parallel lines are supplementary.
