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Good management listens to reasonable demands.
Literal
Good management [subject-なら] legitimate demand [to-に] ear [object-を] lend nominal-ものだ.
~なら ('if X, then...') — here in a characterizing sense, 'if it's good management (then it...).' 耳を貸す ('to lend an ear, listen') is a set phrase. ~ものだ generalizes the predicate, framing it as a defining quality of good management.