For function f of x , which condition implies a horizontal asymptote at y is equal to 31 ?

A horizontal asymptote at y = 31 means that f(x) approaches 31 as x increases or decreases without bound. Choice A states that f(x) approaches 31 as x approaches infinity, so it gives a horizontal asymptote at y = 31. The other choices describe behavior near finite x-values, which does not establish a horizontal asymptote.

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