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

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

A. recharge
B. tectonic force
C. geometrical object
D. temporal entity

Answer: geometrical object