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

The property 'has a committee co-chair' applies to instances of 'Committee', and 'Program committee' is a subclass of 'Committee'. Which class can appear as the value of 'has a committee co-chair' for instances of 'Program committee'?

A. Conference participant
B. Active conference participant
C. Passive conference participant
D. Co-chair

Answer: Co-chair