**Core Concept**
Immunoglobulin E (IgE) plays a crucial role in the pathogenesis of allergic reactions. Elevated levels of IgE are associated with chronic allergies, where the immune system overreacts to harmless substances, triggering an allergic response.

**Why the Correct Answer is Right**
In chronic allergy, the immune system produces increased amounts of IgE antibodies in response to allergens such as pollen, dust mites, or pet dander. These IgE antibodies bind to mast cells and basophils, causing them to release histamine and other chemical mediators, leading to symptoms like itching, sneezing, and congestion. The elevated levels of IgE in chronic allergy contribute to the sustained allergic response.

**Why Each Wrong Option is Incorrect**
**Option A:** Immunoglobulin A (IgA) is primarily involved in mucosal immunity and is not directly associated with chronic allergies.
**Option B:** Immunoglobulin G (IgG) is the most abundant immunoglobulin in the blood and provides long-term immunity against infections, but it is not typically elevated in chronic allergies.
**Option C:** Immunoglobulin M (IgM) is the first antibody to respond to an infection and is not specifically associated with chronic allergies.

**Clinical Pearl / High-Yield Fact**
Remember that IgE is the primary immunoglobulin involved in allergic reactions, and its levels are often used as a marker for diagnosing and monitoring allergies.

**Correct Answer:** C. Immunoglobulin E (IgE)