You will be given a definition of a task first, then some input of the task.
In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").

join a negative and a positive charge through a rare metal in a gas filled globe is known as (A) led (B) High Pressure Sodium (C) incandescence (D) compact florescence
Output:
C