Since the bacteria are round, the right answer is cocci.
The shape of bacteria is a criterion for classifying them. A coccus is a spherical-shaped bacterium, as opposed to the elongated rod form, called a bacillus.
Among the cocci, we find:
* monohulls, simple cocci,
* diplococci, cocci grouped two by two,
* streptococci, chain cocci,
* staphylococci, cocci in clusters.