For Which of the Following Reasons Should We Build Models

Multiple Choice

For which of the following reasons should we build models when designing systems?

A) To help us to visualize a system as it is.
B) To help us to visualize a system as we want it to be.
C) To better understand the system we are developing.
D) To simplify a complex system because we can't comprehend it in its entirety.
E) All of the above.