The correct answers are B and D as they strategically utilize Azure's pricing models to match the company's varied workload needs. Reserved Instances offer substantial cost savings for stable, predictable workloads, while Pay-as-you-go provides the flexibility needed for variable workloads. Additionally, Spot Instances can be effectively used for fault-tolerant applications to achieve further cost reductions without sacrificing operational efficiency. This dual approach ensures optimal cost management across different workload types while maintaining the required operational flexibility.