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

The property 'farther than' applies to instances of 'distance', and 'obukhov length' is a subclass of 'distance'. Which class can appear as the value of 'farther than' for instances of 'obukhov length'?

A. bowen ratio
B. distance
C. runway
D. hummock

Answer: distance