After 19 min of spinning, the Ferris wheel completes one revolution, so any fixed point on the wheel returns to the position at which it started. This point would cover a distance equal to the circumference of the wheel, equal to 2π times the radius r of the wheel.
This means the circumference of the wheel is
(25 m/min) * (19 min) = 475 m
and so the radius of the wheel is
(475 m) / (2π) = r = 75.59 m
which most closely matches D.
