Answer: Scalable architecture design., Leverage managed services when possible.

The correct answers are B and D. AWS architectural design principles emphasize building scalable architectures that can handle changes in load without significant performance impact. This is achieved by using various AWS services and features that support automatic scaling. Additionally, AWS encourages the use of managed services when possible, which handle operational aspects such as provisioning, scaling, and patching, allowing developers to focus on application functionality rather than infrastructure management. Managed services also provide benefits like automatic scaling, patching, and backups. Option A is incorrect as it suggests 'fixed resources' which is not a principle of cloud architecture. Option C is also incorrect because AWS promotes the use of loosely coupled components for better fault isolation and scalability. Option E, 'Design for human interaction,' is not one of the architectural design principles but rather a consideration in user experience design.

Author: LeetQuiz Editorial Team