You have been asked to enable a gradual deployment of your Lambda function in two increments such that 10 percent of your traffic is shifted immediately. After 10 minutes, all traffic is shifted to your deployment. What deployment preference type will meet this requirement?

Answer options:

A.Linear10PercentEvery10Minutes
B.Canary10Percent10Minutes
C.AllAtOnce
D.Lambda function in the PreTraffic hook to move 10 % traffic and all traffic after 10 minutes.

Answer: B
Option A is incorrect as Linear10PercentEvery10Minutes will shift traffic in equal increments with an equal number of minutes between each increment. Every 10 minutes 10% of the traffic is shifted.
Option B is CORRECT as Canary10Percent10Minutes will ensure 10% traffic shifted first and then all traffic is shifted, thereby meeting the requirement also, this ensures traffic is shifted in two increments. 
Option C is incorrect as all traffic will be shifted from the old Lambda function to the updated Lambda function and will not meet the requirement.
Option D is incorrect as pre-hook functions are used to validate and run sanity checks before traffic begins to shift. If this fails, CodeDeploy will abort and rollback the shift.
Reference:
https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/automating-updates-to-serverless-apps.html