Which of the following are characteristics of Amazon VPC subnets?
(Choose two.)
Each subnet maps to a single Availability Zone
A CIDR block mask of /25 is the smallest range supported
Instances in a private subnet can communicate with the internet only if they have an Elastic IP.
By default, all subnets can route between each other, whether they are private or public
V Each subnet spans at least 2 Availability zones to provide a high-availability environment
Explanations:
Each subnet in Amazon VPC is associated with a single Availability Zone (AZ). Subnets are specific to an AZ and cannot span multiple AZs.
The smallest supported CIDR block for an Amazon VPC subnet is /28, not /25. A /28 subnet provides 16 IP addresses, whereas /25 would offer 128 addresses.
Instances in a private subnet can communicate with the internet through a NAT gateway or NAT instance, not necessarily with an Elastic IP. Elastic IP is typically used for public instances.
By default, all subnets in a VPC can route between each other, regardless of whether they are public or private, as long as the necessary routing tables are configured.
A subnet in Amazon VPC is associated with a single Availability Zone, not multiple AZs. However, you can design your architecture to span multiple AZs by creating subnets in each AZ.
I draft that the answer is:
Each subnet maps to a single Availability Zone
I guess:
Each subnet maps to a single Availability Zone