**Core Concept**
Anaphylaxis is a severe, life-threatening allergic reaction that occurs within minutes of exposure to an allergen, leading to symptoms such as stridor, neck swelling, tongue swelling, and hoarseness of voice. It is mediated by the release of histamine and other chemical mediators from mast cells.

**Why the Correct Answer is Right**
The patient's symptoms, including stridor and hoarseness of voice, are indicative of anaphylaxis. The mechanism of anaphylaxis involves the cross-linking of IgE antibodies on mast cells, leading to the release of histamine and other chemical mediators, which cause smooth muscle contraction, increased vascular permeability, and mucus secretion. The involvement of the larynx and tongue suggests that the anaphylaxis is severe and potentially life-threatening.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the patient's symptoms. While angioedema can cause swelling, it typically does not involve the larynx or tongue.

**Option B:** This option is incorrect because epiglottitis is a medical emergency that typically presents with severe sore throat, difficulty swallowing, and high fever, but it is not typically associated with anaphylaxis.

**Option C:** This option is not relevant to the patient's symptoms. While laryngitis can cause hoarseness of voice, it does not typically involve stridor, neck swelling, or tongue swelling.

**Clinical Pearl / High-Yield Fact**
Anaphylaxis is a medical emergency that requires immediate treatment with epinephrine, antihistamines, and corticosteroids.

**Correct Answer: D. Anaphylaxis**