Final answer:
Among the listed approaches for quantifying IT benefits, Performance futures theory is not recognized as a standard method. The others, including real option theory, simulation, external benchmarks, and expert opinion, are all valid approaches.
Step-by-step explanation:
The potential approaches to quantifying the expected benefits of IT initiatives include several methodologies. Of the options provided, real option theory, simulation, external benchmarks, and expert opinion are recognized methods to quantify benefits. However, Performance futures theory is not a standard approach for this purpose.
Real option theory allows for flexibility in decision-making under uncertainty; simulation uses models to predict outcomes; external benchmarks compare with industry standards; and expert opinions rely on the knowledge of experienced individuals. These methods can help organizations and stakeholders make informed decisions regarding IT investments by estimating potential returns and valuing inputs that are not easily quantifiable.