Answer choice (A) is incorrect because the argument does not rely upon this assumption. We know that conductors must earn their authority by winning the orchestra's respect for the artistic interpretations that they are currently pursuing.
This does not necessarily mean that superior conductors devise different interpretations of compositions for different orchestras.
If we negate this and assume that conductors use the same interpretation for different orchestras, the conclusion still stands. The conductor must still win the respect of the orchestra for this interpretation regardless of whether it has been played by other orchestras in the past.
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