According to the PMI-RMP Exam Content Outline1, one of the tasks in the domain of risk identification is to “review project documents, assumptions, and constraints, and understand the project environment and organizational factors to identify risks”. The project charter, work breakdown structure (WBS), and scope statement are essential project documents that provide information about the project objectives, deliverables, requirements, assumptions, and constraints. Without these elements, the risk manager will have difficulty identifying and evaluating the risks that may affect the project. Therefore, the best answer is D. References: 1: PMI-RMP Exam Content Outline, page 7.