A company launched an Amazon RDS for MySQL DB instance. Most connections come from serverless applications, and traffic spikes unpredictably. During high demand, applications receive database connection rejection errors. Which solution will resolve this issue with the least operational overhead?

RDS Proxy is the correct solution because it pools and shares database connections, effectively managing unpredictable traffic spikes and preventing connection rejection errors for serverless applications. It also handles credential management and provides failover support, reducing operational overhead. ElastiCache for Memcached caches query results, which can reduce database load but doesn't solve connection limits directly. Migrating to a higher I/O instance class increases performance but doesn't inherently address the connection limit issue. Multi-AZ provides high availability and disaster recovery, but it doesn't increase the number of concurrent connections a single DB instance can handle or pool connections for serverless applications.