Explanation
LEED BD+C: Multifamily Midrise is the appropriate rating system for residential buildings that are four to eight stories above grade1. Since the project scope includes 60% of the gross floor area, it meets the minimum program requirement of having at least 40% of the gross floor area certified2. The other rating systems are not suitable for this project because they either apply to different building types or heights23.
References:
LEED rating system selection guidance | U.S. Green Building Council2
LEED v4: Building Design + Construction Guide - U.S. Green Building Council3 LEED v4 Rating Systems | USGBC-LI1

The Promote Sustainable and Regenerative Material Resource Cycles impact category in LEED encourages the use of materials that can be continually cycled back into the same system at their end-of-life. This is referred to as moving to cyclical, non-depleting material cycles. It promotes the use of renewable or recyclable materials and reduces waste. Reference: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

Explanation
Strategically locating functional and decorative hardscape on a project site can reduce the amount of on-site impervious area. Impervious surfaces are surfaces that do not allow water to infiltrate into the ground (e.g., concrete or asphalt). By reducing these surfaces, we can increase water infiltration, which helps recharge groundwater supplies and reduces stormwater runoff that can lead to erosion and water pollution. References:
LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

Explanation
LEED credits are weighted based on their potential environmental impacts and human benefits. Those that most directly address these areas are given greater weight in the scoring system. This approach is intended to prioritize actions that have the greatest positive impact on critical environmental issues such as climate change, water resources, biodiversity, air pollution, and human health. References: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources