What perspectives may be used for system modeling?

What perspectives may be used for system modeling?
Ans: (a) An external perspective, where you model the context or environment of the system.
(b) An interaction perspective where you model the interactions between a system and its environment or between the components of a system.
(c) A structural perspective, where you model the organization of a system or the structure of the data that is processed by the system.
(d) A behavioral perspective, where you model the dynamic behavior of the system and how it responds to events.