An Organization Is Creating a VPC for Their Application Hosting

An organization is creating a VPC for their application hosting. The organization has created two private subnets in the same AZ and created one subnet in a separate zone. The organization wants to make a HA system with the internal ELB. Which of these statements is true with respect to an internal ELB in this scenario?

A) ELB can support only one subnet in each availability zone.
B) ELB does not allow subnet selection; instead it will automatically select all the available subnets of the VPC.
C) If the user is creating an internal ELB, he should use only private subnets.
D) ELB can support all the subnets irrespective of their zones.