Explanation
ASHRAE 90.1-2010, Appendix G is the referenced standard for defining the baseline building performance for energy simulation modeling in LEED v4 for Building Design and Construction. The baseline building is a hypothetical building that represents the minimum energy performance required by ASHRAE 90.1-2010, which is a standard for energy efficiency in buildings. The baseline building is used as a benchmark to compare the proposed design of the project and to calculate the percentage of energy cost savings achieved by the project. The baseline building performance is evaluated by following the procedures and assumptions specified in Appendix G of ASHRAE 90.1-2010, such as building envelope, lighting, HVAC systems, service water heating, and renewable energy.
The other options are not relevant to the question, as they are standards for different aspects of green building, such as thermal comfort (ASHRAE 55-2010), air filtration (ASHRAE 52.2-2007), and ventilation (ASHRAE
62.1-2010).
References: LEED v4 Reference Guide for Building Design and Construction, p. 341 1; [ASHRAE website]