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

The property 'spatial relation' applies to instances of 'geometrical object', and 'surface' is a subclass of 'geometrical object'. Which class can appear as the value of 'spatial relation' for instances of 'surface'?

A. plant part
B. geometrical object
C. interplanetary shock
D. titration

Answer: geometrical object