Given: Prove: Three lines BE, AD, and CF are intersected at the midpoint point O. Complete the proof. Suppose that
∠BOC=∠COD. By the vertical angles theorem,
∠AOC=∠COE, and by the transitive property,
∠AOC=∠BOC, which contradicts the given. Therefore, __________.
a) BE is parallel to AD
b) BE is perpendicular to AD
c) BE is congruent to AD
d) BE is bisected by AD
