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

The property 'has option writer' applies to instances of 'option', and 'vanilla option' is a subclass of 'option'. Which class can appear as the value of 'has option writer' for instances of 'vanilla option'?

A. option premium
B. derivatives clearing organization
C. standardized options terms
D. option issuer

Answer: option issuer