The acquisition phase of the system development life cycle (SDLC) is the phase where the organization decides to purchase a new IT system from an external vendor or develop it internally. During this phase, the identified risks will most likely lead to architecture and design trade-offs, as the organization will have to balance the cost, quality, functionality, security, and performance of the new IT system. The organization will have to evaluate the different options and alternatives available, and select the one that best meets the business needs and the risk appetite. The other phases of the SDLC are not as likely to involve architecture and design trade-offs, as they are more focused on implementing, testing, deploying, and maintaining the new IT system. References = Risk and Information Systems Control Study Manual, Chapter 3: IT Risk Response, Section 3.2: IT Risk Response Options, page 133.