Final answer:
The correct answer is C. the effectiveness analysis, which ranks each alternative based on its ability to satisfy user's requirements for a system, focusing solely on meeting goals without considering costs.
Step-by-step explanation:
When a system's alternatives are ranked based on their ability to satisfy user's requirements, it involves an assessment of how effectively each option meets the goals for the system. The most appropriate choice that aligns with this description is C. the effectiveness analysis. Unlike the other options, an effectiveness analysis specifically evaluates the degree to which different options achieve the desired outcomes, independent of the costs.
Cost/benefit analysis, on the other hand, adds a financial dimension to the evaluation, comparing the costs incurred against the benefits received. Both of these analytical tools are vital for decision-making in economics or business, but it is the effectiveness analysis that focuses solely on the capability to meet goals without integrating cost considerations.