If this circle is rotated around the vertical line shown, what three-dimensional figure will be formed?

A) cone

B) cube

C) cylinder

D) sphere

Depending on where the line is with respect to the circle, only two objects can be produced: a sphere and a torus (donut). If the line about rotation intersects the circle perfectly so that the circle is separated into two identical parts, the rotation will be a sphere. Any other rotation will yield a torus.

Because torus isn’t an answer choice, I believe that D is the answer you’re looking for.