**Core Concept**
The patient's symptoms are indicative of an anaphylactic reaction, a severe, life-threatening allergic response that involves multiple body systems. This reaction is mediated by the release of histamine and other chemical mediators from mast cells and basophils.

**Why the Correct Answer is Right**
The patient's symptoms, including edema of the tongue, stridor, dyspnea, hoarseness, and itching, are classic signs of an anaphylactic reaction. The ingestion of peanuts triggers the release of histamine from mast cells in the skin, respiratory tract, and gastrointestinal tract, leading to increased vascular permeability, smooth muscle contraction, and mucus production. This results in the characteristic symptoms of anaphylaxis, including difficulty breathing (dyspnea), swelling of the tongue and lips (edema), and hoarseness.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is likely referring to angioedema, which is a similar condition but is typically localized to the skin and subcutaneous tissue. While angioedema can cause swelling, it typically does not involve the respiratory tract or lead to the same severity of symptoms as anaphylaxis.
* **Option B:** While this option may seem plausible, it is not the most likely cause of the patient's symptoms. The patient's symptoms are too severe and widespread to be explained by a simple food intolerance or allergy.
* **Option D:** This option is unlikely because the patient's symptoms are too severe and widespread to be explained by a simple viral or bacterial infection.

**Clinical Pearl / High-Yield Fact**
Anaphylaxis is a medical emergency that requires immediate treatment with epinephrine (adrenaline) and other supportive measures. Patients who have experienced anaphylaxis should be prescribed an EpiPen or other emergency epinephrine injector and educated on how to use it.

**Correct Answer:** C. Anaphylaxis to peanut.