Your management plans to use AWS Cloudfront to speed up the distribution of content to users from an S3 bucket. They are worried about whether users will get the ideal response when they request for objects from Cloudfront. What would you communicate to them as to how users would get content from Cloudfront?

Answer options:

A.If a user requests an object, only when the entire object is available, it is sent to the user. This is to ensure a correct end-user experience.
B.If a user requests an object, the user is directed to the origin location to retrieve the object.
C.As soon as the first byte arrives from the origin, CloudFront begins to forward the files to the user.
D.Amazon CloudFront will respond with an HTTP 404 error.

Answer – C
The AWS Documentation mentions the following which is done in case the files are not present in the Edge location.
In the edge location, CloudFront checks its cache for the requested files. If the files are in the cache, CloudFront returns them to the user. If the files are not in the cache, it does the following.
a. CloudFront compares the request with the specifications in your distribution and forwards the request for the files to the applicable origin server for the corresponding file type—for example, to your Amazon S3 bucket for image files and your HTTP server for the HTML files.
b.The origin servers send the files back to the CloudFront edge location.
c. As soon as the first byte arrives from the origin, CloudFront begins to forward the files to the user. CloudFront also adds the files to the cache in the edge location for the next time someone requests those files.
Options A and D are incorrect since when Cloudfront receives the first bytes, it is delivered to the user.
Option B is incorrect since an Edge location will deliver the content.
For more information on how Cloudfront works, please visit the following URL:
https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/HowCloudFrontWorks.html