AB is the diameter of a circle with centre O. C and D are two points on the circumference of the circle on either side of AB. such that $$\angle CAB= 42^{\circ}$$ and $$\angle ABD = 57^{\circ}$$. What is difference (in degrees) between the measures of $$\angle CAD$$ and $$\angle CBD$$?

A

105 and 75

B

75 and 105

C

81 and 99

D

99 and 81