Can Checkbox sizes and spacing in quizzes be adjusted?

Hi Aukalen, and thank you for sharing a screenshot of what you are experiencing.

What type of question set-up are you using?

Unfortunately, the question spacing for the buttons isn't something that is editable in the slide master and generally cannot be changed. 

You could look at creating your own buttons and text boxes, but I am aware that this would be more work to execute.

Did you try Rafael's workaround in this thread? 

You can also feel free to submit a feature request, and we can certainly let you know if it makes it onto our feature roadmap in the future!