Which Statement Best Describes the Difference Between the Theoretical Concept

Multiple Choice

Which statement best describes the difference between the theoretical concept of a community and the ways in which communities are delineated in practice?

A) In theory, a community is defined only by abiotic factors of the area; in practice, communities are delineated by biological attributes as well.
B) In theory, communities consist of all species present; in practice, biologists usually study only a subset of the species.
C) In theory, communities can be defined by physical or biological characteristics, but in practice, these characteristics are difficult to measure and are not used.
D) There is no difference between the theoretical concept of a community and how it is defined in practice.