Wayne Is Renting an Efficiency Upstairs from Fields

Wayne is renting an efficiency upstairs from Fields.Wayne decides to go to Europe for four months and lets his friend,Charlie,live in his apartment while he is away,with the understanding that Charlie will pay the rent.Wayne has:

A) assigned the apartment, but Wayne is still liable for the rent.
B) sublet the apartment, but Wayne is still liable for the rent.
C) assigned the apartment, but is not liable for any unpaid rent during Charlie's occupancy.
D) sublet the apartment, but is not liable for any unpaid rent during Charlie's occupancy.