An AWS Solutions Architect designing a solution to store and archive corporate documents has determined Amazon Glacier as the right choice. 
An important requirement is that the data must be delivered within 5 minutes of a retrieval request.
Which feature in Amazon Glacier could help to meet this requirement?

Answer options:

A.Vault Lock
B.Expedited retrieval
C.Bulk retrieval
D.Standard retrieval

Correct Answer – B
AWS Documentation mentions the following:
Expedited retrievals allow you to access data in 1–5 minutes for a flat rate of $0.03 per GB retrieved. Expedited retrievals allow you to quickly access your data when occasional urgent requests for a subset of archives are required.
The Vault Lock and Standard Retrieval are standard with 3-5 hours retrieval time while Bulk retrievals which can be considered the cheapest option have 5-12 hours retrieval time. 
For more information on AWS Glacier Retrieval, please visit the following URL:
https://docs.aws.amazon.com/amazonglacier/latest/dev/downloading-an-archive-two-steps.html