Which three statements are true about named credentials for PaaS Clouds?

Which three statements are true about named credentials for PaaS Clouds?

A.
They must be defined as global credentials.

B.
They must be defined as host credentials.

C.
They must be defined as target credentials.

D.
They must be applied to hosts in the infrastructure zone.

E.
They must be applied to the infrastructure zone.

F.
They must be applied to PaaS pools.
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Explanation:
http://docs.oracle.com/cd/E24628_01/doc.121/e28814/cloud_paas_setup.htm#EMCLO
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