Bacteria that can grow in the presence or absence of oxygen (o2) are called hints bacteria that can grow in the presence or absence of oxygen (o2) are called microaerophiles obligate aerobes facultative anaerobes obligate anaerobes

The answer is facultative anaerobes.

The easiest way to obtain the answer is by looking for the etiology and meaning of "facultative", which in biology refers to something that can live under different and opposite circumstances.

The other way of finding the answer is by descartig options.

Hope it helped,

BioTeacher101

cell regulation is conducted by special proteins.