All the following veins drain into internal jugular vein except: (A) Facial vein, (B) Lingual vein, (C) Retromandibular vein, (D) Superior thyroid vein
Answer is C. Retromandibular vein
Internal Jugular vein

It is the continuation of sigmoid sinus
Tributaries of IJV

1. Inferior Petrosal sinus
2. Ferial
3. Lingual
4. Pharyngeal
5. Superior thyroid vein
6. Middle thyroid vein