Task: Property Constraint Reasoning (ontology: Sciences/Biology)

The property 'skeleton of' applies to instances of 'anatomical structure', and 'surface structure' is a subclass of 'anatomical structure'. Which class can appear as the value of 'skeleton of' for instances of 'surface structure'?

A. banks of superior temporal sulcus
B. anatomical collection
C. food propellant
D. anatomical structure

Answer: anatomical structure