Transversal t cuts parallel lines a and b as shown in the diagram. Which equation is necessarily true? A figure shows a set of 2 parallel lines, line a and line b, which are crossed by line t, and a set of parallel lines are cut by a transversal. Each of the parallel lines cut by the transversal has 4 angles surrounding the intersection. A. m∠1 = m∠2 B. m∠4 = m∠6 C. m∠1 m∠5 = 90° D. m∠3 m∠5 = 180° E. m∠7 = m∠8