Hello student,

I hope you are doing well.

1). The three pairs of equal parts in two triangles ABC and BOD are:

CO = DO (given)

OA = OB (given)

Angle COA = Angle DOB ( As opposite angles are equal when two lines intersect)

2).  So by SAS congruency rule,

Triangle COA is congruent to Triangle DOB

that is

Triangle AOC is congruent to Triangle BOD

Hence, option B is correct.

I hope it helps.