As shown in the figure, AB is the chord of circle O, OC perpendicular  AB and it intersects circle O at point C. Connect OA, OB, BC, if angle ABC = 25.0, then the size of angle AOB is ()
Choices:
A:80°
B:90°
C:100°
D:120°
Please directly answer the question and provide the correct option letter, e.g., A, B, C, D.
Question: As shown in the figure, AB is the chord of circle O, OC perpendicular  AB and it intersects circle O at point C. Connect OA, OB, BC, if angle ABC = 25.0, then the size of angle AOB is ()
Choices:
A:80°
B:90°
C:100°
D:120°
Please first conduct reasoning, and then answer the question and provide the correct option letter, e.g., A, B, C, D, at the end.
Question: As shown in the figure, AB is the chord of circle O, OC perpendicular  AB and it intersects circle O at point C. Connect OA, OB, BC, if angle ABC = 25.0, then the size of angle AOB is ()
Choices:
A:80°
B:90°
C:100°
D:120°