How does the parallel structure of these sentences help Roosevelt achieve his purpose?

Read the excerpt from Roosevelt’s State of the Union address.

Fortunately, there are only a few Americans who place appetite above patriotism. The overwhelming majority realize that the food we send abroad is for essential military purposes, for our own and Allied fighting forces, and for necessary help in areas that we occupy.

How does the parallel structure of these sentences help Roosevelt achieve his purpose?

a. The varied structure serves to keep the audience alert and engaged.
b. The consistent structure emphasizes Roosevelt’s expectations for farmers.
c. The varied structure reflects the various ways the food could be used.
d. The consistent structure reinforces how the food sent abroad should be used.