Dear Land Kruzer,
Resetting your Windows 10 PC means that all the system files are deleted and then restored to their originals. All your desktop applications are removed from your PC, so you have to reinstall and reconfigure each of them after the reset process is done. Files that are not saved are moved to the C:\Windows.old directory. You can recover files from this directory after the reset.
And the answer of your question is: Files in your user profile folder (C:\Users\YourName) are saved as expected but files stored directly in the users folder (C:\Users) and not in a specific user profile are NOT saved. The Public user profile (C:\Users\Public) is NOT saved as well.
PS 1: If you haven't installed the Operating System on D drive, then you will not lose any files in D: drive
PS 2: I recommend you to backup your data by yourself and put them in the External Hard Drive or anywhere you preferer.
Keep me updated