Correct Answer: Argon

Solution : The correct option is Argon .

Argon is a noble gas with the atomic number 18 and the chemical symbol Ar. It is colourless, odourless and tasteless, accounting for approximately 0.93% of the Earth's atmosphere. Because of its inert qualities and non-reactive nature, Argon (Ar) is used in welding, light bulbs, laboratory, artefact preservation, medical treatments, energy-efficient windows, gas lasers, and deep-sea diving. Other noble gases in Group 18 (VIII-A) of the periodic table include the elements He (Helium), Neon (Ne), krypton (Kr), Radon (Rn), and Xenon (Xe).