Opting for a NoSQL database and adjusting read/write capacity units in anticipation of workload demands is a recommended approach to manage performance requirements while controlling costs. It allows developers to estimate the required throughput, ensuring that the application can handle the expected traffic with consistent performance. This option enables fine-grained control over resource allocation, which aligns with the goal of handling predictable performance demands and cost-efficiency. While triggering a function on data stream events can respond to database changes, it does not inherently optimize CRUD operation performance or cost. Creating a read replica can enhance read throughput but does not directly impact write operations or address the proactive provisioning strategy. Similarly, augmenting the memory of a database instance may assist with caching but does not offer precise control over CRUD operation scalability and cost like proactive capacity provisioning does.