Which of the following are architectural best practices for the AWS cloud?

The emphasis on elasticity and scalability as architectural best practices for the AWS cloud is essential due to the dynamic nature of cloud environments. Elasticity refers to the ability of a system to automatically adapt to workload changes, scaling resources up or down as needed. This capability is fundamental in cloud architecture, allowing businesses to handle varying user demands efficiently and cost-effectively.

Scalability complements elasticity; it indicates the system's ability to grow and manage increased loads without sacrificing performance. This means a well-architected application can expand resources seamlessly to accommodate an influx of traffic or scale back during quieter periods, optimizing resource usage and cost.

By focusing on these principles, businesses can improve their operational efficiency, ensuring they only consume the resources necessary to meet their current demand while maintaining performance standards.

In a cloud context, options that include single points of failure, manual intervention, static resource allocation, or complex network designs detract from the ideal cloud architecture since they can create bottlenecks, limit flexibility, and increase operational overhead. Thus, emphasizing elasticity and scalability is key to achieving the full benefits of cloud computing.