In the context of a LEED project, the charrette is a meeting of stakeholders, project team members and others to establish project objectives. The charrette is a collaborative and participatory process that involves brainstorming, discussing, and generating ideas and solutions for the project's sustainability goals, design strategies, performance targets, and evaluation methods. The charrette is usually held at the early stages of the project to ensure alignment and integration among all parties involved. The LEED Green Associate Candidate Handbook states that one of the steps in the integrative process is to "conduct a preliminary LEED assessment with key project team members, including owner" [1, p. 12]. Reference: LEED Green Associate Candidate Handbook, [Charrette | Whole Building Design Guide]

Explanation
Renewable Energy Certificates (RECs) are tradable, non-tangible energy commodities that represent the environmental attributes of one megawatt-hour of electricity generated from renewable sources, such as wind, solar, hydro, or biomass1. RECs can be purchased by anyone, regardless of their location or utility provider, to support the development of renewable energy and reduce their carbon footprint2. RECs can also help projects earn points for the LEED v4 Innovation credit for Green Power and Carbon Offsets, which requires the purchase of at least 50% of the total building energy use from renewable sources or offsets for a minimum of five years3.
References:
Using Renewable Energy for LEED Certification
Renewable Energy Certificates For Green Building Explained
LEED v4, Renewable Energy, and Carbon Offsets

Explanation
Green Cleaning is a plan that is implemented after occupancy to ensure that the building is maintained in a way that reduces the environmental and health impacts of cleaning products, equipment, and practices. Green Cleaning is part of the LEED v4 Operations and Maintenance rating system, and it includes credits for purchasing sustainable cleaning products and materials, using green cleaning equipment, implementing an indoor integrated pest management program, and developing a green cleaning policy1.
References:
LEED v4: Operations and Maintenance Guide1, pages 36-41

Explanation
The USGBC administers the LEED credentialing programs, which include the LEED Green Associate and the LEED AP with specialty credentials. The USGBC does not administer the LEED exams, the LEED rating systems development, or the LEED project certification.
References:
The LEED Green Associate Candidate Handbook states that "The U.S. Green Building Council (USGBC) administers the LEED credentialing programs related to green building practice" 1, page 3.
The same handbook also states that "The Green Business Certification Inc. (GBCI) administers the LEED professional credential exams" 1, page 3.
The LEED AP with Specialty Candidate Handbook states that "The U.S. Green Building Council (USGBC) is responsible for the development of the LEED rating systems" 2, page 3.
The same handbook also states that "The Green Business Certification Inc. (GBCI) administers project certification for all commercial and institutional projects pursuing LEED certification under any of the current rating systems" 2, page 3.

Explanation
The Integrative Process Credit in LEED v4 requires the project team to implement an integrative process that enables them to discover unique opportunities for enhancing project performance and environmental benefits1. The project team should identify and use opportunities to achieve synergies across disciplines and building systems2.
References := Integrative process | U.S. Green Building Council, LEED Integrative Process Credit Explained - Projectific, Inc.