Explanation
Signoff formalizes the agreement and confirmation that the requirements are accurate and complete. Answer:
C is incorrect. This isn't a valid statement, as signoff shows the agreement of the stakeholders that the requirements are complete.
Answer D is incorrect. This isn't a valid statement.
Answer B is incorrect. This isn't a valid statement, as the agreement is among the stakeholders, not between the project manager and the project sponsor.

Explanation
Requirements must be communicated before they are managed. Tracy must communicate the requirements to the stakeholders for their consent and approval before managing the requirements.
Answer A is incorrect. Before Tracy decomposes the requirements, she should have the approval of the stakeholders.
Answer B is incorrect. To begin managing the requirements, Tracy needs the approval and consent of the stakeholders.
Answer C is incorrect. This isn't a valid statement, as the best thing to do is to gain the approval of the stakeholders first.

Explanation
Once the ideas have been recorded, then the business analyst should rate the ideas and distribute the list to the appropriate stakeholders.
Answer C is incorrect. The business analyst doesn't record the ideas as requirements.
Answer B is incorrect. This isn't a valid statement as time and cost estimates aren't needed for each idea generated in the session.
Answer A is incorrect. The project manager doesn't need, necessarily, to discuss the brainstorming ideas.

Explanation
Risk identification is not an input to the plan business analysis activities. The four inputs to the plan business analysis activities are organizational process assets, business analysis approach, stakeholder list, roles, and responsibilities, and the business analysis performance assessment.
Answer B is incorrect. The organizational process assets are inputs to the plan business analysis activities.
Answer C is incorrect. The business analysis approach is an input to the plan business analysis activities.
Answer A is incorrect. The stakeholder list, roles, and responsibilities is one of the four inputs to the plan business analysis approach.