What is the glass used in tube lights and test tubes made of?

Correct answer: (e) None of the above/More than one of the above

Explanation

Ordinary soda-lime glass, used for tube lights, is made by melting silica (sand) with sodium carbonate and calcium carbonate, usually with some broken glass (cullet) added. Test tubes use borosilicate glass (silica with boron oxide), which withstands heat.

Since the glass comes from more than one of the materials listed, the answer is "More than one of the above".