Final answer:
With AWS Cloud, users benefit from no upfront costs and the pay as you go model, allowing for flexible and cost-effective scaling without worrying about underused resources. However, AWS manages the physical infrastructure and both AWS and users share responsibility for security.
Step-by-step explanation:
When working with the AWS Cloud, there are several management and operational headaches that are not your concern. This is because AWS provides a managed infrastructure with various benefits that relieve users from certain responsibilities.
Firstly, no Upfront costs (C) is one of the advantages you have with AWS. There is no need to invest heavily in data centers or servers before you start your projects. You can start with what you need and scale as your requirements grow, paying only for the resources you consume.
Secondly, AWS operates on a pay as you go model (B), which means you only pay for the resources you use. This negates the risk of burning costs for non-running resources because if you stop using a service, you typically stop paying for it. This pricing model provides significant flexibility and cost-efficiency.
Contrary to options A and D, you should not assume complete control over the physical infrastructure because this is managed by AWS (Option A is incorrect), and you should also actively focus on security (Option D is incorrect), as AWS operates with a shared responsibility model where AWS manages the security of the cloud and customers are responsible for security in the cloud.