Choose the correct contraction (short form of is).
ASomebody’s knocking at the door.
BSomebody else’s knocking at the door.
CSomebody else is knocking at the door.
DSomebody elses knocking at the door.
ASomebody’s knocking at the door.
BSomebody else’s knocking at the door.
CSomebody else is knocking at the door.
DSomebody elses knocking at the door.