The project manager should review the historical information and lessons learned from last year's project to justify the new budget estimate. This is because the project manager used an analogous estimating technique, which is based on the costs of similar projects in the past. By reviewing the historical information and lessons learned, the project manager can explain to the project sponsor how the costs of the new project were derived, what assumptions and risks were considered, and how the three-point estimating technique was applied. This can help the project sponsor understand the rationale behind the budget estimate and increase their confidence in its accuracy and validity. The project manager can also use this opportunity to discuss the benefits and value of the new project and how it aligns with the organizational strategy and objectives. References: PMBOK Guide, 6th edition, section 7.2.2.4, page 262, Free PMP Exam Sample Question 04 (Earned Value)