Which two statements are true about network groups?

You want to control network traffic among your DBaaS instances.
Which two statements are true about network groups?

A.
By default, the DBaaS instances in a network group are accessible from hosts outside
the network group.

B.
You can add a DBaaS instance to a network group, but this enables communication only
within this network group.

C.
You can add a DBaaS instance to a network group, thus enabling communication with
all other DBaaS instances both inside and outside thenetwork group.

D.
You can create a network group to enable unrestricted communication among your
DBaaS instances.

E.
DBaaS prevents network groups from having unrestricted communication among DBaaS
instances.

Explanation:
Network groups provide a method for VMs to be grouped together forcommunications and
firewall rules. You can define network groups to allow VMs within agroup to communicate
with each other, while also preventing those VMs fromcommunicating outside the group.
Note:
Access rule. Access rules define the permitted paths of communication for VMs that are
within a network group. You can define an access rule to enable a specific path of
communication between two network groups, orbetween a network group and a specified
list of IP addresses.
http://www.oracle.com/webfolder/technetwork/tutorials/obe/cloud/dbaas/OU/Intr
oDBaaS/ConfiguringNetworkSettings/ConfiguringNetworkSettings.html#section2s2