Final answer:
The writ used by the court to order First Bank to turn over the funds in Sam's account is known as a writ of garnishment, used to claim debtor's property when held by a third party.
Step-by-step explanation:
The writ the court will use ordering First Bank to turn over to it the funds in Sam's account is a writ of garnishment. A garnishment is a legal procedure through which a creditor can collect what a debtor owes by reaching the debtor's property when it is in the hands of someone other than the debtor.
This is different from a writ of execution, which allows for the seizure of the debtor's property directly. A writ of attainder is unconstitutional as it is a legislative act that singles out an individual or group for punishment without a trial, and therefore is not applicable in this context. Since the term attachment has already been confirmed as not being the answer, we can eliminate that option as well.