The suggested answer is B, C.
Cisco WAN Automation Engine (WAE) primarily focuses on network design, planning, and optimization, leveraging network abstraction which includes topology, configuration, and traffic details. One of its main use cases is integrating with Cisco XTC (Crosswork Traffic Controller) to enhance network control and optimizations. Additionally, WAE is commonly used for performing what-if analysis, where it can simulate and analyze network failures, topology changes, and traffic demands to aid in decision-making and planning.