In which part of the oral cavity has thinnest mucous membrane:: (A) Buccal mucosa., (B) Labial mucosa., (C) Floor of the mouth., (D) Soft palate.
Answer is C. Histologically mucosa of the floor of mouth is non-keratinized, thinnest and loosely adherent to the underlying structures. Loose attachment to the underlying tissue provide free mobility to the tongue.