Implementing a green roof to manage rainwater is the best answer because it directly supports Sustainable Sites strategies. A vegetated roof can reduce runoff volume, slow peak discharge, improve rainwater quality, reduce heat island effects, provide habitat benefits, and create usable or visual open space depending on design. Optimizing energy performance is important, but it belongs mainly to Energy and Atmosphere. Rapidly renewable or responsibly sourced materials relate to Materials and Resources. High-efficiency plumbing fixtures belong to Water Efficiency. Since the question asks specifically how to maximize points in the Sustainable Sites category, the project team should prioritize site-based strategies such as rainwater management, heat island reduction, site assessment, open space, and habitat protection. A green roof is the option most aligned with SS goals.