Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'extracellular space'?

A. That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid.
B. A cellular component that consists of an indeterminate number of proteins or macromolecular complexes, organized into a regular, higher-order structure such as a polymer, sheet, network or a fiber.
C. A cellular anatomical entity that is part of an axoneme consisting of a doublet microtubule.
D. The part of a synapse that is part of the post-synaptic cell.

Answer: That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid.