For this we would suggest to use the ‘Open-ended’ question instead of the Q&A (upvoting) question. With upvoting users can upvote each other responses and only the most upvoted will be shown on screen. This question also doesn’t work with the Response filter so messages can’t be deleted manually by the presenter.
When using the Open-ended question you can also use the Response filter. You can copy the ‘Link to Response Filter’ displayed in the ‘Settings’. If you open this on any other device (for instance the smartphone of the presenter) you can see all responses coming in. The presenter can now decide which input you’d like to display on screen. You can delete certain messages which you for instance already treated. It is also possible to have the ‘Auto-accept’ toggle activated in the response filter. When this toggle is activated you won’t be able to use the response filter.