Answer:
d. Serverless computing.
Step-by-step explanation:
Chris is concerned about deploying an application to a cloud service provider and being locked in technologically so that his organization would have to stay with that cloud service provider in order to run that application.
Therefore, the use of Serverless computing should allow for an easier migration from one cloud service provider to another.
This is because, serverless computing has to do with a cloud computing model which gives the machine resources tasks to take care of servers on behalf of clients.