Hi Sebastiano,
This list has always been a point of confusion inside of CA.
Generally, different customers will have only one or two options to select in this list based on their contract.
As you are a CA employee, you see all possibilities that the customers would see.
For example, customer 1 might see "CA Siteminder B to B - Multi-Platform" with their contract while customer 2 might see "CA Siteminder B to C - Multi-Platform" with their contract and so on but you will see every possible contract.
Basically, there is no difference in the products included underneath regardless of which you select.
The policy server under any of the options will be the same policy server(as long as you select the same release version) for example.
When I am looking for a download I just pick one.
Hope this answers your questions.
Sincerely,
Jonathan Taft
CA Technologies SSO Support
1-800-225-5224