Task: Property Constraint Reasoning (ontology: Earth_Environment/EnvironmentOntology)

The property 'regulated by' applies to instances of 'process', and 'environmental system process' is a subclass of 'process'. Which class can appear as the value of 'regulated by' for instances of 'environmental system process'?

A. process
B. spatiotemporal region
C. increased amount
D. antagonist

Answer: process