GRE Text Completion: ETS Official Practice 150-GRE OP150:填空 - 6FVZ49GG66VF0R4BO

Although the compound is abundant in the environment at large, its presence in the air is not ____________; only in the form of underwater sediment does it cause damage. A. trivial B. detectable C. deleterious D. substantive E. detrimental F. inconsequential