I use a multiple-choice grid in a google form. How can I dieactivated all checkboxes in this form? 
I started to do some tests with the Google Forms configurations and settings.
Sadly it would not be possible to remove the checkboxes as you suggest. Mainly due to the way the Forms interface works or is presented, for example:
Due to the rows and columns functionality. It might be a better idea to introduce a drop down menu if you still want to provide multiple choices, for example:
I can see an option in the future to change the style or design of the multiple choices. You can send feedback for something similar in the future here:
Or
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