A rectangle is inscribed in a semicircle of radius 1 unit. If its two vertices lie on the diameter, for largest size, then its dimensions are
A. Length `=sqrt(2)`, breadth `=(1)/(sqrt(2))`
B. Length `=sqrt(3)`, breadth `=(1)/(2)`
C. Length `=(2sqrt(3))/(sqrt(2))`, breadth `=(1)/(3)`
D. Length `=(1)/(sqrt(2))`, breadth `=sqrt(2)`