A child presents with a bluish, translucent, fluctuant mass on the floor of the mouth. The most likely diagnosis is:

Correct answer: C. Ranula

• A. Lymphangioma presents as a soft, compressible, multilobulated mass, often with a pebbled surface; it is not typically blue-translucent like a ranula.
• B. A mucocele is a mucus extravasation phenomenon occurring most commonly on the LOWER LIP (not the floor of the mouth) due to minor salivary gland duct trauma.
• C. Correct. A ranula is a mucus extravasation or retention cyst involving the sublingual gland, presenting as a blue, translucent, fluctuant swelling on the floor of the mouth. The term 'ranula' (Latin for frog belly) reflects its appearance.
• D. A dermoid cyst is a developmental cyst that can appear on the floor of the mouth but presents as a doughy, non-translucent mass, often midline.