Task: Property Constraint Reasoning (ontology: Earth_Environment/EnvironmentOntology)

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

A. metallic material
B. paper product
C. biotransformation of coal
D. anatomical structure

Answer: anatomical structure