The first step for a new project manager-especially one taking over midstream-is to understand the business objectives and rationale for the project. The business case outlines the expected benefits, strategic alignment, and value proposition, which are essential for understanding how success is defined. According to the PMBOK Guide - Seventh Edition, the business case is a key input to initiating and monitoring a project's continued alignment with organizational strategy. Option B is premature without understanding the current baseline and project justification. Option C is detailed-level work; business context is needed first. Option D is helpful but comes after understanding the foundational documentation. References: PMBOK Guide - Seventh Edition, Value Delivery System and Business Case PMI Guidelines for Managing Transitions Between Project Managers -