Final answer:
The duty that should not be assigned to ensure records are updated only for authorized transactions is opening and closing all bank accounts, as this task is administrative and does not involve direct transaction updates.
Step-by-step explanation:
In order to ensure that all records are updated only for authorized transactions, appropriate individuals should be assigned duties that segregate financial responsibilities to prevent fraud and errors. The only option provided that should not be an assigned duty to ensure updated records for authorized transactions is A. Opening and closing all bank accounts. This task does not directly update records but instead deals with the administrative aspect of bank accounts. The other duties, such as B. Preparing the bank reconciliation, C. Approving bank deposits, and D. Approving electronic transfers of funds directly relate to the recording and authorization processes that update records for transactions.