$\textbf{Answer: D}$
$\textbf{Explanation}$
$\underline{\textbf{Fair:}}$ Its a noun, adverb or an adjective.
$\underline{\textbf{Fare:}}$: It's a verb or a noun.
$\textbf{Fair}$ means without any cheating or trick.
$\textbf{Fare}$ means cost or charge levied on something.