1 (1A) 2 (2A) 17 (7A) 18 (8A)
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Incandescent light bulb filaments are best preserved by filling the bulb with a low density, non-reactive gas. From which group of elements on the periodic table is this gas most likely selected?
Possibilities:
- 1 (1A)
- 2 (2A)
- 17 (7A)
- 18 (8A)

18 (8A)