Which type of bacteria can be found in pairs, chains, squares of four, cubes of eight, or grapelike clusters?

Cocci are spherical bacteria, and they commonly occur in arrangements such as pairs, chains, groups of four, cubes of eight, or grape-like clusters. Bacilli are rod-shaped, while spirilla are spiral-shaped; pili are structures that extend from some bacteria. Therefore, the correct choice is coccus.

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