A helicopter flying along the path `y=7+x^((3)/(2))`, A soldier standint at point `((1)/(2),7)` wants to hit the helicopter when it is closest from him, then minimum distance is equal to (a) `(1)/(6)(sqrt2)/(3)` (b) `(1)/(2)` (c) `(1)/(3)sqrt((2)/(3))` (d) `sqrt((5)/(2))`
A. `1/2`
B. `1/3sqrt(7/3)`
C. `1/6sqrt(7/3)`
D. `sqrt5/6`
