What Is the Major Distinction Between Primary and Secondary Metabolites

What is the major distinction between primary and secondary metabolites?

A) Primary metabolites are produced by animals; secondary metabolites are produced by plants.
B) Primary metabolites are produced by plants; secondary metabolites are produced by animals.
C) Primary metabolites are produced by eukaryotes; secondary metabolites are produced by prokaryotes.
D) Primary metabolites are produced by the breakdown of molecules; secondary metabolites are produced during the construction of larger molecules.
E) Primary metabolites are produced during ordinary activities; secondary metabolites are produced under special circumstances.