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

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A kudos would greatly help

Tuhin