Task: Question Generation
Input (English): Background Paragraph: Noble gases are also used to fill the glass tubes of lighted signs like the one in the Figure below . Although noble gases are chemically nonreactive, their electrons can be energized by sending an electric current through them. When this happens, the electrons jump to a higher energy level. When the electrons return to their original energy level, they give off energy as light. Different noble gases give off light of different colors. Neon gives off reddish-orange light, like the word “Open” in the sign below. Krypton gives off violet light and xenon gives off blue light. 
Story: John wanted to make some lighted signs for his business. To that end, he chose noble gases, neon, krypton, and xenon. First, he kept the noble gases in containers. He called it step A. Then he passed electric current through them. He called it step B. In the process, he came up with three signs, sign A, sign B, and sign C. Sign A used neon. Sign B used krypton, and sign C used xenon.
Output (English): Which sign would have violet color, sign B or sign C?