@elad33 ,
Is this on a mobile app or inside a browser? Is it the legacy (old) quizzes or the new quizzes?
This information I write below is about the legacy quizzes inside a browser.
For browsers, the default font size is set to 1rem, which is the the size of the root element. For my installation of Chrome, that is 16px, which is about 12pt. It is this because under Chrome's Settings > Appearance menu, I have the Font size set to Medium (recommended).
If I change that to Small, then the font size on my quizzes changes to 12px or about 9pt. If I make it very small, the font size changes to 9px or about 7pt. Large is 20px, about 14.5pt, and Very Large is 24px or about 18pt. These settings control every page inside every window inside the browser, not just within Canvas.
I have not set a font size on my text inside the quiz question. As expected because of the 1rem setting, when my browser is set to medium font size, my text shows up as 12pt.
When I change the browser settings to large, the font size in Canvas changes to 15pt, even though 15pt is not an option. The approximation before for 16px was about 14.5pt, so the 15pt makes sense.
Most people hopefully don't change the font size setting, but if I manually set a font-size in the quiz question, then it gets locked in at that size.
If I think setting it to 12pt is a good idea so it's a bigger font because 10pt is too small, what I'm really doing is hurting the student who needs (or prefers) the larger font. I tend to need larger fonts to be able to read things clearly and by manually setting the font size in the question, you're taking that choice out of the user's hands and putting it into the developer's hands.
This is why I think putting actual font sizes on the toolbar is a bad idea and they should have only put relative sizes on there -- if anything. When I design, I make conscious efforts to remove any font-size or other crud from my HTML, preferring to let the defaults rule the day.
In case the point is missed, if the content creator goes through and manually sets that font size, then it's going to ignore attempts by the administrator to enlarge the font. If somehow the method of creating the questions forced it to 10 pt, which is not the default of the standard Canvas, setting it to something else may be problematic.
Setting it to something larger may cause issues for mobile devices, where there is limited space on the screen.
Another possibility for what is happening is that faculty think it's too small when they look at the quiz editor. When you edit a question, it looks okay, but when you save it and it shows up in the list of questions, then it's smaller than normal. On that screen, the default font size (for my setup with medium font size specified in the browser) is 12.6px, which is about 10pt, and it is small to my liking. However, when I preview the quiz, then it's the default size specified in the browser settings. It's possible that a faculty member saw that screen and thought it was too small.
Before you change anything, I would dig more into what's actually going on. Edit a quiz question and see if the instructor has specified a font size for the questions that looks small. Create a new question and see what the font size is. Check the browser settings. Check out the question in mobile.
The default font size from Canvas is to be the normal sized. If it's small, then something else is going on and I try to figure that out.
Often times, people who design want it to look good on their computer setup, without taking into consideration how it looks for everyone else. Anything the admin does is going to effect everyone and that may not be a good outcome.
Canvas really does screw things up sometimes. A few weeks back, I thought the quiz questions looked entirely too small, despite everything I just wrote about their appearance now. It's fixed now, though. If you're self-hosting and haven't updated to the latest code, you may be running with bugs that have been fixed. If you're self-hosting, then I would start by upgrading there.
My main point is that I'm not seeing what you're describing, at least in a browser, and that you may want to investigate more before you make changes that are going to affect everyone and not necessarily in a good way.
