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

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

A. behavior
B. biomarker
C. figure
D. material entity

Answer: material entity