A Company Uses Alibaba Cloud SLB and Auto Scaling at the Same

Multiple Choice

A company uses Alibaba Cloud SLB and Auto Scaling at the same time, hoping this combination can help save O&M cost and provide a stable and reliable system. However, because they do not have relevant experience, the company's engineers listed some precautions based on their understanding, and turned the list to you for advice. As an expert of Alibaba Cloud, you tell them only _______________ is correct.

A) SLB instances must have Health Check enabled, or they cannot be used together with Auto Scaling
B) All ECS instances under the same SLB instance must be running on the same operating system
C) All backend servers under the same SLB instance must be in the same Scaling Group
D) All backend servers under the same SLB instance must have the same configuration