The project manager must first review the contract or agreements to determine if such rate adjustments are allowed or pre-defined. The PMBOK Guide - Seventh Edition stresses the importance of understanding procurement and contract terms when managing requests that affect cost or scope. Only after confirming the legal framework can the project manager take appropriate next steps, whether renegotiation or formal change control.
Option A is premature before understanding contractual obligations.
Option C delegates responsibility without understanding the terms.
Option D implies negotiation without confirming legal allowances.
References:
PMBOK Guide - Seventh Edition, Procurement and Planning Considerations
PMBOK Guide - Sixth Edition, Section 12.1: Plan Procurement Management
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