Unfortunately, it is not possible to edit the answers using the Edit Quiz button after the quiz is published,

If it's a spelling mistake of course you can download the quiz as an Excel file and edit the columns that appear in it to match the real option,

But if the answer is different than you intended you will need to create a new quiz.

This is due to the fact that users have already taken the action of answering the old answers and the system has already received them.