Explanation
The only input to the task of defining assumptions and constraints is stakeholder concern.
Answer C is incorrect. Requirements aren't inputs to the task of defining assumptions and constraints.
Answer B is incorrect. Prioritized requirements aren't inputs to the task of defining assumptions and constraints.
Answer A is incorrect. The business case isn't an input to the task of defining assumptions and constraints.

Explanation
The plan-driven approach has the most business analysis work at the beginning of the project or during the start of a project phase. This approach has a high amount of formality and detail for all areas of the business analysis duties, requirements gathering, and monitoring.
Answer D is incorrect. This statement is not true about the plan-driven approach. Answer C is incorrect. This statement describes requirements prioritization.
Answer A is incorrect. Plan-driven approaches typically discourage change and they work to refine the requirements over time to prevent errors and omissions.

Explanation
Change-driven approaches focus more on frequency of communication than on formal documentation. Official documentation is often in writing, but informal communication takes precedence over more formal written communication.
Answer D is incorrect. The best answer is frequency of communication, not the type of communication.
Answer A is incorrect. The best answer is frequency of communication, not correct communication - which is important, but it's not the best selection for the QUESTION.
Answer C is incorrect. The best answer is frequency of communication, not message of communication.
Having the correct message and correct communication channels are important, but these aren't the best selection for this QUESTION.

Explanation
Request for information (RFI): A formal elicitation method intended to collect information regarding a vendor's capabilities or any other information relevant to a potential upcoming procurement.

Explanation
The predictive approach to delivery is a more formal approach and hence can cause a rework of tasks and activities already completed when a change is implemented as well as of the activities required to assess the proposed change on the whole.
A lot of requirements elicitation and analysis done in the early phases of a project follow the predictive approach. This means when a change is required during later phases of this type of project, there is often a higher impact on the time, cost, and effort required. An adaptive approach will try and minimize the impact of changes with iterative implementations from an early stage of the project. This approach typically lends itself to a less formal and more adaptable approach to manage the impact of change that is introduced during the life cycle of the project. Within the adaptive approach to delivery, the idea of an evolutionary delivery may also reduce the need for a formal impact assessment to be performed when a change is proposed to a requirement.