If an administrator often needs to manage multiple ECS instances in an Alibaba Cloud VPC through the Internet.
Which of the following solutions can meet this need at low costs and without affecting system security.
A . None of these answers are correct.
B . Choose an ECS instance from VPC and make it as the bastion host And then, apply an EIP and bind it to this ECS instance. After that the administrator can manage other ECS instances through this bastion host.
C . Modify the VPC Security Group policy, to allow access from the Internet.
D . Bind an EIP to each of the ECS instances, and Jog on to each of these ECS instances to manage them.