Explanation/Reference:
Explanation:
B: Database services should be created as UNIFORM services, meaning the service is offered by every available instance running in the specified server pool. If your application requires a SINGLETON service, then, to use Oracle Database QoS Management in management mode, the service must run in a server pool that has a maximum size of one. If you use a SINGLETON service in a server pool that has a maximum size greater than one, then Oracle Database QoS Management reports a configuration violation.
C: Initial QoS configuration includes:
Installing and Configuring Oracle Grid Infrastructure for a Cluster

Creating and Configuring Server Pools

Creating and Configuring an Oracle RAC Database

Enabling Oracle Database QoS Management

Incorrect Answers:
E: It must be policy managed. When you use DBCA to create an Oracle RAC database, you select policy- managed for the database, and choose the server pools which the database instances should run in.
References: https://docs.oracle.com/cd/E11882_01/server.112/e24611/install_config.htm#APQOS157
https://docs.oracle.com/database/121/APQOS/wlm_strats.htm#APQOS341