The parallel on a sports card
No scan can tell a base card from a Silver Prizm, so you answer the parallel yourself.
The parallel is yours to answer
No scan reliably tells a base card from a Silver Prizm. They are the same artwork with a different finish.
So we leave the answer to you instead of guessing. The picker ranks the options by how many sellers name each one.
A card has exactly one parallel, and it usually drives the price more than anything else.