Which organisms are pus-forming bacteria that grow in clusters resembling bunches of grapes?

• A. Staphylococcus species
• B. Bacillus species
• C. Clostridium species
• D. Streptococcus species

Answer: (A)

Verified step by step guidance

1. Understand the term 'pus-forming bacteria': These are bacteria that cause infections leading to the accumulation of pus, which is a thick fluid composed of dead white blood cells, bacteria, and tissue debris.
2. Recall the morphology and arrangement of bacteria: 'Clusters resembling bunches of grapes' refers to the way bacterial cells group together under the microscope.
3. Identify the genus known for forming grape-like clusters: Staphylococcus species are Gram-positive cocci that characteristically form irregular clusters similar to bunches of grapes.
4. Compare with other options: Streptococcus species form chains, Bacillus species are rod-shaped and often form chains or single cells, and Clostridium species are also rod-shaped anaerobes, so none of these form grape-like clusters.
5. Conclude that the pus-forming bacteria growing in clusters resembling bunches of grapes are Staphylococcus species.