The presence of pus is a sign of which of the following?

• A. Fungal colonization
• B. Bacterial infection
• C. Viral replication
• D. Allergic reaction

Answer: (B)

Verified step by step guidance

1. Understand the nature of pus: Pus is a thick fluid composed mainly of dead white blood cells, tissue debris, and bacteria or other pathogens.
2. Recognize that pus formation is typically a result of the body's immune response to infection, particularly involving neutrophils fighting off invading microorganisms.
3. Identify that bacterial infections often trigger the accumulation of pus due to the immune system attacking bacterial pathogens.
4. Contrast this with fungal colonization, viral replication, and allergic reactions, which generally do not produce pus as a primary symptom.
5. Conclude that the presence of pus is a hallmark sign of bacterial infection because it reflects the immune system's response to bacterial invasion.