Internal orifice of branchial Fistula is located at:: (A) Lower third of neck over anterior border of starnocleidomastoid, (B) Floor of external auditory canal, (C) Posterior tonsillar pillar, (D) Anterior to tragus on the ipsilateral side
Answer is C. Branchial festula represents 2nd branchial cleft:

Internal orifice: Anterior aspect of posterior tonsillar pillar.
External orifice: Lower third of neck over anterior border of sternocleidomastoid.