Answer:
Option C, anthrax bacteria
Step-by-step explanation:
All options i.e amoeba, paramecium and aloe vera plant have eukaryotic cell which have well defined nucleus and layered organelles.
A prokaryotic cell lacks well defined nucleus and also do not have some essential cell organelles. Along with this the cell organelles and nucleus do not have envelope or outer layer.
Only bacteria and archae have prokaryotic cells.
Hence, option C is correct