I accidentally clicked on something  & now Yahoo answers is displaying with a  much smaller font. How can I fix this?

Make text in your web browser bigger or smaller: https://help.yahoo.com/kb/sln2937.html

Go into the settings for your browser and adjust the zoom magnification. Depending on what browser you use, the steps to find that feature will vary.

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Your question belongs in Computers & Internet>Software as it's currently in Yahoo Products>Yahoo Answers and not applicable to this subcategory, which is for questions about how YA works and the rules here (and thus decreases your chances of getting many useful answers).

Moving your question can be done by clicking Edit (pencil icon for mobile)>Edit category just beneath your question, then selecting the category that's appropriate for the topic.

Press Ctrl and then + at the same time that should Increase the Font Size you probably Accidentally Pressed something that made it go Smaller Easy Fix tho 

Not a problem with yahoo.  You can only adjust your don't on your device.  And since we don't know what device or operating system you have we can't answer especially since you posted this in the wrong category.  Post in hardware software with details if you really want an answer.