Which of the following are characteristics of Amazon VP…

Which of the following are characteristics of Amazon VPC subnets? (Choose two.)

A.
Each subnet spans at least 2 Availability Zones to provide a high-availability environment.

B.
Each subnet maps to a single Availability Zone.

C.
CIDR block mask of/25 is the smallest range supported.

D.
By default, all subnets can route between each other, whether they are private or public.

E.
Instances in a private subnet can communicate with the Internet only if they have an Elastic IP.

Explanation:
Even though we know the right Answers it is sometimes good to know why the other Answers are wrong.
A:
Is wrong because a subnet maps to a single AZ.
C:
Is wrong because /28 is the smallest subnet, amazon takes first four and last addresses per subnet.
E:
Is wrong because a private subnet needs a NAT appliance.