The Figure Shown Below Diagrams Three Pathways for the Metabolism

The figure shown below diagrams three pathways for the metabolism of glucose. Pathway ________ is most likely to be used for biosynthesis because it can be used to ________.

A) 1; generate glucose
B) 2; make carbon backbones of many lengths
C) 3; make carbon backbones of many lengths
D) 1; make carbon backbones of many lengths
E) 3; generate glucose