The correct answer is B because cross-functional teams in Scrum are not optimized to work on only one component or one technical layer of a system. A cross-functional Scrum Team has all the skills necessary to create value each Sprint and deliver a usable Increment. This means the team should be capable of working across the different skills and disciplines needed to complete Product Backlog items according to the Definition of Done.
If a team is organized around only one component or specialty, it creates handoffs, dependencies, and silos.
Those conditions reduce agility and make it harder to deliver a complete Increment each Sprint. Scrum instead favors teams that can collaborate across analysis, design, development, testing, and other needed capabilities so they can produce finished product value rather than partial technical output.
Cross-functionality supports self-management and reduces delays caused by waiting on other specialists or teams. It helps the Scrum Team focus on outcomes instead of isolated activities. In Scrum, the goal is not local optimization of a single layer or function. The goal is delivering complete, useful, high-value Increments frequently and transparently.