Given OC = AB
OC = OB since both are radii.
Therefore OB = AB.
Since angles opposite to equal sides are equal. Therefore,
Angle OCB = Angle OBC and Angle OAB = Angle BOA
Statement 1 Angle COD = 60 degrees. Not sufficient. Since we cannot determine angle COB or angle OCB.
Statement 2 Angle OCB = 40 degrees. Not sufficient Since we cannot determine angle COB
Both together helps us determine Angle COB and angle BOA = 180 - angle COD - angle COB
Therefore, answer is C
A kudos would greatly help