Given: y || z Prove: m∠5 m∠2 m∠6 = 180° Angles Lines Statements Reasons y || z ∠1 ≅ ∠3 m∠2 = m∠3 m∠5 = m∠4 ∠5 ≅ ∠6 m∠6 = m∠4 Which statement completes the proof? a) A b) B c) C d) D