Your team currently uses Bigtable as their database backend. In your application's app profile, you notice that the connection to the Bigtable cluster is specified as single-cluster routing, and the cluster’s connection logic is configured to conduct manual failover when the cluster is unavailable. You want to optimize the application code to have more efficient and highly available Bigtable connectivity. What should you do?

A. Set up Memcached so that queries hit the cache layer first and automatically get data from Bigtable in the event of a cache miss. B. Increase the Bigtable client’s connection pool size. C. Configure a Dataflow template, and use a Beam connector to stream data changes. D. Configure the app profile to use multi-cluster routing.