In trade finance, an exporter can seek financing from multiple banks based on the same invoice sent to the importer. What could potentially solve this pain point? A. A distributed ledger that could be accessed by multiple banks to verify the invoice information B. A digital signature on a Smart Contract verifying that the importer is genuine, and the invoice is not fake C. A Proof-of-Stake algorithm that would first require the exporter to put up some cryptocurrency upfront to make sure the invoice is not fake D. A smart contract that automatically pays the exporter once an invoice has been submitted