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

The property 'is implemented by' applies to instances of 'algorithm', and 'Rank-invariant set normalization' is a subclass of 'algorithm'. Which class can appear as the value of 'is implemented by' for instances of 'Rank-invariant set normalization'?

A. histologic grade according to AJCC 7th edition
B. probability distribution estimation task
C. software
D. Number of users unrestricted

Answer: software