Maintaining balance while a system matures through development is difficult when there is design instability. Which statement completes the sentence?

• A. Adequate funding and stable requirements.
• B. Clear performance specifications.
• C. Mature prototypes.
• D. NOT application, manufacturing and Insufficient.

Answer: (D)

Design stability across development is what allows a program to progress without constantly reworking plans, tests, and budgets. When the design is unstable, changes ripple through requirements, interfaces, and production plans, making it hard to keep pace, manage risk, and coordinate across teams. The statement that best completes the sentence signals that this difficulty isn’t confined to any single area like application, manufacturing, or resource levels; it points to design instability itself as the overarching disruptor. In other words, even if other factors such as funding, clear specifications, or mature prototypes are in place, ongoing instability in the design can still derail balance during maturation. The other options describe conditions that would help stabilize progress, thereby reducing the difficulty, rather than explaining why the difficulty persists due to instability.