Read Replicas require a transactional storage engine an…

Read Replicas require a transactional storage engine and are only supported for the ____ storage engine.

A.
OracleISAM

B.
MSSQLDB

C.
InnoDB

D.
MyISAM

Explanation:
http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html