Which of the following is a hypersensitive response to a particular substance by the immune system?

• A. Phagocytosis
• B. Inflammation
• C. Allergy
• D. Complement activation

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the concept of hypersensitivity in immunology. Hypersensitivity refers to an exaggerated or inappropriate immune response to an antigen or substance that can cause tissue damage or disease.
2. Step 2: Review the options given: Phagocytosis, Inflammation, Allergy, and Complement activation. Identify which of these represents an immune system reaction that is specifically a hypersensitive response.
3. Step 3: Recall that phagocytosis is a process where immune cells engulf and destroy pathogens, which is a normal immune function, not a hypersensitive reaction.
4. Step 4: Recognize that inflammation is a general immune response to injury or infection, which can be part of hypersensitivity but is not itself a hypersensitive reaction.
5. Step 5: Understand that allergy is a classic example of a hypersensitive response where the immune system reacts excessively to harmless substances (allergens), causing symptoms like sneezing, itching, or more severe reactions.