A student is preparing a sugar-water solution to make rock candy. When the student continues to add sugar to the solution, no additional sugar dissolves. Which kind of solution is the student preparing?

A) The student is preparing a saturated solution.
B) The student is preparing a supersaturated solution.
C) The student is preparing an unsaturated solution.
D) We cannot tell if the student is preparing a saturated, a supersaturated, or an unsaturated solution.