In Amazon ElastiCache, the failure of a single cache node can have an impact on the availability
of your application and the load on your back-end database while ElastiCache provisions a
replacement for the failed cache node and it get repopulated. Which of the following is a solution
to reduce this potential availability impact?

A.
Spread your memory and compute capacity over fewer number of cache nodes, each with
smaller capacity.

B.
Spread your memory and compute capacity over a larger number of cache nodes, each with
smaller capacity.

C.
Include fewer number of high capacity nodes.

D.
Include a larger number of cache nodes, each with high capacity.

Explanation:
In Amazon ElastiCache, the number of cache nodes in the cluster is a key factor in the availability
of your cluster running Memcached. The failure of a single cache node can have an impact on the
availability of your application and the load on your back-end database while ElastiCache
provisions a replacement for the failed cache node and it get repopulated.
You can reduce this potential availability impact by spreading your memory and compute capacity
over a larger number of cache nodes, each with smaller capacity, rather than using a fewer
number of high capacity nodes.
http://docs.aws.amazon.com/AmazonElastiCache/latest/UserGuide/CacheNode.Memcached.html