Task: SWRL-based Rule Reasoning (ontology: Earth_Environment/EnvironmentOntology)

Suppose an individual ?x satisfies: iron group element atom(?x). Which conclusion is one valid inferred conclusion?

A. d-block element atom(?x)
B. chromium group element atom(?x)
C. yttrium atom(?x)
D. rare earth metal atom(?x)

Answer: d-block element atom(?x)