Edwina: True appreciation of Mozart’s music demands that you hear it exactly as he intended it to be heard; that is, exactly as he heard it.
Edwina's Conclusion (it follows)
We should hear Mozart's music on 18th century instruments.
Edwina's Evidence (since)
Mozart heard his music on 18th century instruments, and true appreciation of Mozart's music requires that we hear it as he intended it to be heard.
Alberto's Implied Conclusion
Maybe Mozart didn't intend for his music to be heard the same way he was hearing it played?
Alberto's Evidence (after all)
Mozart wrote at a time when the performer was expected not just to interpret but to modify the written score.
Evaluate
The classic answer choices for rebuttals on Method are: - highlights dubious assumption - suggests alternate explanation - shows faulty implications - raises an overlooked consideration
In this case, Alberto is raising the overlooked consideration that Mozart didn't intend to perform a piece of music the way it was in the written score.
His era expected performers to put their own spin on the piece (interpret it) and even to improvise/revise it a bit (modify the score).
Because of that, Alberto can highlight the dubious assumption that Mozart wants his music to be played just as he heard it (whether that be on 18th century instruments or as written on the score).
Goal
Let's look for any answer that matches.