Select the most correct answer: The device name /dev/sd…

Select the most correct answer: The device name /dev/sda1 (within Amazon EC2) is _____

A.
Possible for EBS volumes

B.
Reserved for the root device

C.
Recommended for EBS volumes

D.
Recommended for instance store volumes

Explanation:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDeviceStorage.html
The root device is typically /dev/sda1 (Linux) or xvda (Windows).