This article explains how to add, edit the text of, reorder and remove the Answer Choices in a multiple choice question that has already been added to a survey.
...
Select My Apps in the top menu
Select Categories
You arrive in the Categories (Lists) App
This displays:
List fields you have created from within the Categories (Lists) App
Every Master Question that your Multiple Choice survey questions with Shared Answer Choices are based on
Every Multiple Choice survey question that you have created from scratch (i.e. not using Shared Answer Choices)
Click Edit to edit the Category (List) you want to change the Answer Choices within
You arrive on the Edit Category (List) page
From here you can
ADD additional Answer Choices
EDIT the text of an Answer Choice
REORDER the Answer Choices: Note: do this by changing the priority number rather than by cutting & pasting the answers themselves
REMOVE Answer Choices
Follow the steps in the next section…
...
Press Remove Item
Press Save