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

The property 'causal relation between processes' applies to instances of 'occurrent', and 'spatiotemporal region' is a subclass of 'occurrent'. Which class can appear as the value of 'causal relation between processes' for instances of 'spatiotemporal region'?

A. occurrent
B. obsolete Mediterranean forests, woodlands, and shrub biome
C. collection of organisms
D. obsolete caprine dairy product

Answer: occurrent