Though OP never actually stated that the machine can perfectly predict the future. If that’s the case, then yes, you should just take box B. But we’re not given any information about how it makes its prediction. If @Sordid@sh.itjust.works is correct in assuming it’s a 50-50, then their strategy of taking both is best. It really depends on how the machine makes its prediction.
This is a bit of a strange question, because an amendment is just that - an amendment. You don’t list amendments in your first draft of a constitution, you list articles. Amendments are changes made to the constitution after it’s ratified.