Choice Eliminator and Choice Eliminator Lite is a Google Forms add-on.

This add-on will eliminate selected choices of multiple choice, list, or check box type of questions when a users submits.

Choice Eliminator is designed for light use only, and may be unreliable when multiple people are taking the form at the same time. Use Dropdown type of questions instead of multiple choice for better reliability.

Choice Eliminator will eliminate options from a multiple-choice, dropdown, or checkbox type of question. Great for signing up for time slots or having students choose topics without doubling up. Version 2 uses spreadsheet functions to keep the results up-to-date, besides being more reliable when using limits, this allows you to restore eliminated choices and set the order.