The described behavior-agreeing externally while internally opposing-matches the accommodative (also known as smoothing or yielding) conflict resolution style. This approach involves one party giving in to maintain harmony, even at the cost of their own interests.
According to the PMI's conflict resolution techniques:
Accommodating (or smoothing): One party gives in to maintain harmony.
Avoiding: Withdrawing from conflict and not addressing it.
Collaborating: Working together to find a win-win solution.
Competing (Combative): Pursuing one's own concerns at the other's expense.
The team members in the scenario were not withdrawing (so not Avoidant), and certainly not arguing (so not Combative). They weren't actively resolving either, which rules out Collaborative. Thus, the correct resolution style is Accommodative.
References:
PMBOK Guide - Sixth Edition, Section 9.5.2.1 (Interpersonal and Team Skills: Conflict Management) PMI Talent Triangle: Leadership - Conflict Resolution Techniques
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When faced with a major process change in HR acquisition, especially one that implies longer processing times, it is essential for the project manager to first assess the impact of this change on the project's objectives and deliverables. By reviewing the project management plan, the project manager can determine the appropriate adjustments to the project schedule, resources, and strategies to mitigate any negative effects on the project's timeline and costs. This proactive approach aligns with the principles of effective project management, which include flexibility and responsiveness to changes within the project environment.
: = The PMBOK guide emphasizes the importance of continuously monitoring and controlling project work to address changes and implement necessary adjustments1. Additionally, the role of HR in managing changes during mergers and acquisitions, as outlined in professional business analysis resources, supports the approach of assessing impacts and planning accordingly234.

When the project manager identifies that the delay on the critical path was caused by the client, it is essential to formally document this and then seek a discussion with the client. This supports transparency, allows for resolution, and protects the contractor from inappropriate penalties.
Per the PMBOK Guide - Seventh Edition and PMI's Contract Management standards, documenting the root cause and opening a dialogue is the first proper step in addressing contractual disputes.
Option B is a valid legal step, but only after engagement and documentation.
Option C refers to an internal party (sponsor) who may not be relevant here.
Option D may support analysis but does not immediately address the contractual issue.
References:
PMBOK Guide - Seventh Edition, Governance and Delivery Performance Domains PMI Practice Standard for Project Contracts