Choice "B" is correct. System testing through independent verification of transaction processing results represents one of the most effective methods to reduce the risk of incorrect processing of transactions in a newly installed accounting system.Choice "a" is incorrect. Although segregation of duties is a foundational control that helps ensure that transactions are not controlled by one individual from beginning to end, the separation of transaction authorization, recordkeeping and asset custodial duties does not reduce the risk of incorrect processing of transactions.Choice "c" is incorrect. Authorization of transactions is a strong control over the validity or legitimacy of transactions, but does not necessarily reduce the risk of incorrect processing. Choice "d" is incorrect. Asset safeguarding is an important security measure but does not provide effective reduction of the risk for incorrect processing.