When calculating for a building's efficiency, which key performance metrics are considered?

B is the correct choice because assessing a building's efficiency fundamentally revolves around its resource usage and sustainable practices. Energy consumption measures how much energy is used for heating, cooling, lighting, and operating the building, reflecting its overall energy efficiency. Water usage metrics indicate how effectively a building uses water resources, pointing to potential conservation measures. Material recycling denotes the efficiency in terms of the lifecycle of materials used in construction and operation, emphasizing sustainability and minimizing waste.

Focusing on these metrics aligns with sustainability goals and environmental impact reduction, which are critical in modern building practices. Therefore, understanding and improving these factors directly contributes to enhancing a building's overall efficiency.