Answer:
Streptococcus
Step-by-step explanation:
Bacteria can be grouped based on their physical characteristics. Cocci are spherical shaped bacteria, and based on their arrangement can be grouped as:
Diplococci: they appear in pairs
Streptococci: they appear in a chain
Staphylococci: they appear as a cluster (grape-like)
Streptococcus is a bacteria genus known to cause many types of diseases. They grow in pairs or chains.
Note that: staphylococci and streptococci are used denote to denote the arrangement of the cells, Staphylococcus and Streptococcus are bacteria genus. They are named so based on the shape and arrangement of their cells.