This question fits the Process domain because it concerns phase transition, scope control, backlog management, and operational governance. The scenario shows two issues: unsupported backlog work is being requested outside approved requirements, and ownership of production support is unclear. PMI's PMP Examination Content Outline stresses managing project scope, engaging stakeholders appropriately, and ensuring clarity in processes and responsibilities. The best response is to review the approved production support plan and associated processes with the business and team members, while also working with the business and product manager to reprioritize backlog items for the next phase. That addresses both governance gaps in a structured way.
Option A is helpful but weaker than E because it does not explicitly involve the business in reprioritization.
Option B incorrectly shifts support ownership to the product manager without reference to the approved plan.
Option D is excessive and disruptive because reopening a completed phase is usually not the first or best response. PMP logic favors following the approved support process and formally reprioritizing new or deferred work into the next phase rather than performing informal, uncontrolled additions. Therefore, C and E are the strongest choices.