Task: Property Constraint Reasoning (ontology: Business_Finance/Financial_Industry_Business_Ontology)

The property 'has original issue discount amount' applies to instances of 'bond', and 'callable bond' is a subclass of 'bond'. Which class can appear as the value of 'has original issue discount amount' for instances of 'callable bond'?

A. RegularCouponSchedule
B. monetary amount
C. municipal debt source of funds
D. StepEvent

Answer: monetary amount