Which of the following is a definition of virtualization?

Which of the following is a definition of virtualization?

A.
Virtualization is a method to organize servers in a more efficient manner to double the number of accessible users

B.
Virtualization is a set of techniques for hiding software resources behind hardware abstractions.

C.
Virtualization is a set of techniques for hiding hardware resources behind software abstractions.

D.
Virtualization is a method to structure data in a more efficient manner with less cost to the user.