A company is running a batch application on Amazon EC2 instances. The application consists of a backend with multiple Amazon RDS databases. The application is causing a high number of reads on the databases. A solutions architect must reduce the number of database reads while ensuring high availability. What should the solutions architect do to meet this requirement?

1. Add Amazon RDS read replicas.
2. Use Amazon ElastiCache for Redis.
3. Use Amazon Route 53 DNS caching.
4. Use Amazon ElastiCache for Memcached.