Question

where does an aws vm instance find its os files?
template
ami
san
boot volume

Explanation:

In AWS, an Amazon Machine Image (AMI) contains the template for the operating system and other software needed to launch an instance. A VM instance (EC2 instance) uses the AMI to get its OS files. A template is a general term and not specific to AWS OS file sourcing. SAN (Storage Area Network) is for storage networking, not OS file sourcing for AWS instances. A boot volume is part of the instance's storage but the initial OS files come from the AMI.

Answer:

B. AMI