In a four-bar chain it is required to give an oscillatory motion to the follower for a continuous rotation of the crank. For the lengths of 50 mm of crank and 70 mm of the follower, determine theoretical maximum length of coupler. The distance between fixed pivots of crank and followers is________________________?

A. 95 mm
B. slightly less than 95 mm
C. slightly more than 95 mm
D. 45 mm
E. none of the above