Which of the following statements are true regarding emulation? (Choose TWO correct answers.)

Which of the following statements are true regarding emulation? (Choose TWO correct answers.)
A . Emulation can only provide distinct hardware components but no complete virtual machines.
B . Emulation requires changes to the guest operating system.
C . Emulation reimplements a whole computing system in software.
D . Emulation allows operating systems to be run on foreign architectures.
E . Emulation is one of the most resource efficient virtualization techniques.

Answer: C,D