Select the word or phrase that is redundant and can be removed without changing the meaning of the text. Despite the fact that the Hindenburg was filled with seven million cubic feet of highly flammable and combustible hydrogen gas, the German airship had a smoking lounge.

The phrase "flammable and combustible" is redundant in this context. Both words convey the same idea that the hydrogen gas can catch fire, so one of them can be removed for clarity and conciseness. The revised sentence could simply state: "Despite the fact that the Hindenburg was filled with seven million cubic feet of highly flammable hydrogen gas, the German airship had a smoking lounge."