Which of the Following Is the Best Definition of a Microstate

Which of the following is the best definition of a microstate as it pertains to entropy on the molecular level?

A) the state-for example, solid, liquid, or gas-of a small cluster of atoms or molecules
B) a property, such as temperature, of a small cluster of atoms and molecules that is independent of how the property was achieved
C) the set of vibrational, rotational, and translational energy levels in a system
D) a unique specification of the vibrational, rotational, and translational states of a single molecule in a system
E) a unique specification of the vibrational, rotational, and translational states of all of the particles in a system