Explanation
The conventional building process stages can vary depending on the type, size, and complexity of the project, but a general overview can be found in this article. According to the article, the stages are:
Planning: This is the stage where the project idea is conceived, the feasibility and budget are assessed, the design and engineering are developed, the permits and approvals are obtained, and the contractors and subcontractors are hired. This stage involves various disciplined practitioners on project teams, such as architects, engineers, surveyors, estimators, project managers, and lawyers.
Sitework and foundation: This is the stage where the project site is prepared, the utilities are connected, the excavation and grading are done, and the foundation is laid. This stage involves mainly civil engineers, site workers, foundation contractors, and building inspectors.
Rough framing: This is the stage where the structural components of the building are erected, such as walls, floors, roofs, stairs, and windows. This stage involves mainly carpenters, framers, roofers, and window installers.
Exterior construction: This is the stage where the exterior finishes of the building are applied, such as siding, brickwork, stucco, insulation, doors, and landscaping. This stage involves mainly exterior contractors, painters, landscapers, and door installers.
MEP (Mechanical, Electrical, Plumbing): This is the stage where the mechanical systems of the building are installed and tested, such as heating, ventilation, air conditioning (HVAC), plumbing, electrical wiring, lighting fixtures, fire alarms, and security systems. This stage involves mainly mechanical engineers, electricians, plumbers, HVAC technicians, and fire protection specialists.
Finishes and fixtures: This is the final stage where the interior finishes of the building are applied, such as drywall, flooring, cabinets, countertops, appliances, furniture, and accessories. This stage involves mainly interior designers, drywallers, flooring installers, cabinet makers, countertop installers, appliance installers, and furniture movers.
As you can see from this overview, each disciplined practitioner on project teams is involved in different stages of the conventional building process, depending on their expertise and role. However, they are also required to collaborate and coordinate with each other throughout the design process, which spans from the planning stage to the finishes and fixtures stage. The design process is an iterative and interactive process that involves creating, reviewing, and refining the design plans and specifications to meet the project goals and requirements1. Therefore, the answer is D. As required during design process.
References:
Building a House Step by Step: A Guide From Start to Finish
What Is Disciplined Agile? - Project Management Institute

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]