I have doubts about intercontract communication

I have read that:

In order to call an inline action, that is to call an action of contract A from contract B, there is a need to set some special permission. In this case, the Ram payer for the action in contract B must-have “accountname [email protected]” permission in its active. In a case, if account C needs to call an action in account A through a contract in account B, then account C need to set the [email protected] in its active.

But I observed that:

1. Contract B must-have “accountname [email protected]” permission in its active even to call function from contract A & not “accountname [email protected]” permission in its active.
2. If account C needs to call an action in account A through a contract in account B, then account C need to set the
   [email protected] in its active. This is true but is there any
   alternative that C can use contract B to call action from contract A
   without changing its permissions. Because in dapp it is not feasible
   for every user to do that.

I’m confused a bit about the all this. Can anyone please give me a clear guidance? Also, in accordance with the v2.0Latest version