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

The property 'has measure' applies to instances of 'debt pool', and 'mortgage pool' is a subclass of 'debt pool'. Which class can appear as the value of 'has measure' for instances of 'mortgage pool'?

A. prepayment speed
B. credit spread
C. debt securities market maker
D. pool factor

Answer: prepayment speed