Choice "D" is correct. Decision support systems are computer-based information systems that provide interactive support to managers or others during the decision-making process.
Choice "c" is incorrect. Management reporting systems provide managers with the information needed for day-to-day decision making.
Choice "b" is incorrect. A formalized system is a generic term used to describe any system operating in proper or regular form.
Choice "a" is incorrect. A structured system is a system in which each program within a system is independent of other programs within the system. This enables programming teams to work independently on different programs within the same system.