Question 1353 Deck General

The correct answer is C) gaseous natural gas. In liquefied natural gas (LNG) tanks, the gas above the liquid is the gaseous form of the natural gas itself. This gaseous natural gas is present to maintain the necessary pressure in the tank and prevent the liquid LNG from boiling off. The tank is designed to minimize the loss of the LNG through evaporation. The other options are incorrect because: A) very dry air would not be present in an LNG tank, B) an inert gas like nitrogen or argon is not used, and D) nitrogen alone would not be the appropriate gas above the LNG liquid.