How to unsubscribe multiple emails for same person after survey completed from one of their emails

I don't know of an automated way to do this; you'll have to do some manual work with your Directory or email list as the responses come in.
Do you have the full XM Directory feature or just the Contacts tab?
Basically, when someone responds, you'll have to search for the email address they did not respond from, and either opt that address out of the list, or (if the address is not in another email list) delete the non-responding email.
My account has XM Directory so I can only help with that if you need further assistance; I don't know exactly how to do this in an account with the Contacts tab.

Thank you for your response. I have this pictured below that is the XM Directory feature I believe. Would it work with that?

Possibly, but your approach will depend on how your brand admin has set up permissions for your account in XMD. When you click on one of the lists shown and select a member in the list, does it allow you to edit or change the list member at all?

Yes I can edit the lists

OK, then you might be able to remove or opt out the list members from there.

Once the student answers the survey I programmed it so they are unsubscribed from the list with the email they used to take the survey, but it will not let me unsubscribed them if they are in the list more than once with other unique emails.
I am not sure how to remove or opt them out of the list with their other emails as you mentioned above. Where would I do that? Thank you again for your help

You'll have to do this manually by searching your list for the email address they did not respond from, then view the "Lists" tab, and either select "Remove from list" or "Opt-out of list" as shown below.

Okay thank you!!