Final answer:
The term for the tooth surface closest to the tongue on all teeth is the d) lingual surface.
Step-by-step explanation:
The tooth surface closest to the tongue on both the anterior and posterior teeth is known as the lingual surface. This term specifically refers to the aspect of a tooth that faces towards the tongue. In the context of dental terminology, various surfaces of the teeth are named according to their position in the mouth. The buccal surface refers to the side of the tooth adjacent to the cheeks, typically for the posterior teeth, and the labial surface pertains to the tooth surface facing the lips, which is commonly used for anterior teeth. The mesial surface is the side of the tooth that is towards the midline of the face, while the distal surface is the side farthest from the midline.
Considering these definitions, the correct answer to the student's question is d) Lingual surface.