In an SM $($State Machine$)$ chart, state assignment is essential before deriving next state and output equations. Which of the following is true regarding state assignment?

Ops: A$.$ State assignment in SM charts involves assigning binary codes to each state.

B$.$ One$-$hot state assignment is preferred for SM charts implemented with gates and flip$-$flops.

C$.$ State assignment in SM charts is not necessary if programmable gate arrays $($PGAs$)$ are used.

D$.$ State assignment in SM charts is done by placing state codes inside the decision boxes.