Why Correct: Hydrogen gas catalyzes the hydrogenation of unsaturated vegetable oils, converting liquid oils into solid or semi-solid Vanaspati ghee.
Distractor Analysis: Nitrogen serves as an inert blanketing gas in food packaging to prevent oxidation. Carbon dioxide is a greenhouse gas and fire extinguishing agent. Neon is a noble gas used in lighting and advertising signs.
Takeaway: Nickel or palladium catalysts typically facilitate industrial hydrogenation reactions at high temperatures and pressures.