The right option is; A. shape
Eubacteria (also called the true bacteria) are unicellular prokaryotic microorganisms that usually have rigid cell walls which is composed of peptidoglycan and flagella for movement. Eubacteria have various characteristics and they are grouped into three types based on their shape. They include; spirilla, cocci and bacilli. Spirilla have a spiral or comma shape, cocci have a round shape, while bacilli have a rod shape.