Task: Class Definition Understanding (ontology: Earth_Environment/EnvironmentOntology)

Which of the following definitions best describes 'groundwater'?

A. A mixed forest which is subject to tropical climatic conditions.
B. A marine reef which is primarily composed of self-adhered or conglomerated mussel shells.
C. The thickness of some snow.
D. Underground water which is located in pore spaces found in rock or unconsolidated deposits such as soil, clay, or gravel.

Answer: Underground water which is located in pore spaces found in rock or unconsolidated deposits such as soil, clay, or gravel.