The agents which cause allergy are known as

Options

A. allergens
B. antigens
C. analgesics
D. narcotics

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe agents that cause allergies.

2. **Defining Allergy**: An allergy is defined as an excessive immune response to a specific substance (antigen) that the body mistakenly identifies as harmful.

3. **Identifying the Correct Term**:
- The options provided are:
- A) Allergens
- B) Antigens
- C) Analgesics
- D) Narcotics
- We need to determine which of these terms specifically refers to agents that cause allergies.

4. **Analyzing Each Option**:
- **A) Allergens**: These are specific antigens that trigger allergic reactions. They are indeed the agents that cause allergies.
- **B) Antigens**: While all allergens are antigens, not all antigens cause allergies. Therefore, this term is too broad.
- **C) Analgesics**: These are pain-relieving medications and do not cause allergies.
- **D) Narcotics**: These are also pain-relieving drugs and are not related to allergies.

5. **Conclusion**: The correct answer is option A, "Allergens," as they are the specific agents that cause allergic reactions.

**Final Answer**: The agents which cause allergy are known as **Allergens**.

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