Can I register multiple users in access control?

In my case I need to specify multiple user groups. For example, group A can access apps A, B, and C, but not apps D and E. Group B can access apps C, D, and E, but not apps A and B. In this case, the C app is accessible by both groups. I don't want to set separate username and password for each app. I want to use only two accounts, one for group A and one for group B. To do that, I need to be able to set up two accounts for a C app. In summary, I would like to know how to set up multiple accounts for access to one app. If this is not possible, I would like to know if there are any support plans.