In the convex quadrilateral ABCD, the diagonals AC and BD meet at O and the measure of angle AOB is $$30^\circ$$. If the areas of triangles AOB, BOC, COD and AOD are 1, 2, 8 and 4 square units respectively, what is the product of the lengths of diagonals AC and DB in square units?

A

60

B

56

C

54

D

64