The code segment below is intended to swap the values of the variables num$1$ and num$2$ using a temporary variable temp.

temp $=$ num$1$;

num$1=$ num$2$;

missing code

Which of the following can be used to replace missing code so the code segment works as intendded?

num$2=$ temp;

num$2=$ num$1$;

temp $=$ num$1$;

temp $=$ num$2$;