Edx courses on UC Application

Hi, i took a neurobiology course on edx. I’m adding it to the non a-g extra coursework area in the Activities and Awards section. Are the UCs going to ask for me to submit my certificate to prove I took the course? Not sure if I should pay extra to get the certificate?

If it is a non a-g course, the UC’s will not care about the course in their application review so highly unlikely they will ask for documentation.