WILL GIVE BRAINLIEST! DO NOT COPY ANSWERS OFF INTERNET Which statement justifies why ∠EBC measures 90°?

Given: angles ABD and DBC are complementary

Point B is on line AE between points A and E, point B is on line FD between points F and D, ray BC intersects with line AE at point B, line FD intersects with line AE at point B, the measure of angle ABD is 50 degrees, and it is given that angles ABD and DBC are complementary.

A linear pair is two adjacent, supplementary angles.
The sum of the measures of complementary angles is 90 degrees.
If two angles are vertical angles, then they are congruent.
Alternate interior angles are congruent.

Option A    

Step-by-step explanation:

angles ABD and DBC are complementary                     given

angle ABD=50 degrees                                                   given

angles ABD and DBC = 90 degrees                              def. of complementary

angle DBC = 40 degrees                                                algebra (90-50=40)

angles EBF and ABD are vertical angles               vertical angles postulate

angle EBF is congruent to angle ABD                           def. of vertical angles

angle EBF = 50 degrees                                                def. of congruence

angles EBF and ABF are a linear pair                            def. of linear pair

angles EBF and ABF are supplementary                       def. of linear pair

angles EBF and ABF = 180                                              def. of supplementary

angle ABF = 130 degrees                                                algebra (180-50=130)

angles ABF and EBD are vertical angles                   vertical angles postulate

angles ABF and EBD are congruent                               def. of vertical angles

angle EBD = 130 degrees                                                def. of congruence

angles CBE + DBC = EBD                                                diagram

angles CBE + DBC = 130 degrees               transitive property of congruence                

angle ABD = 90                                            algebra (130-40=90)

B is needed in the process, but the main statement that actually does the justification is A, so option A