Final answer:
In France, during times of poor harvests, bakers would stretch their bread by adding fillers such as sawdust or hay, which acted as extenders when grain was scarce. Therefore, the correct option is C.
Step-by-step explanation:
During times of poor harvests in France, when grain was scarce and food shortages were common, people had to come up with strategies to make their bread last longer. One approach was c. French bakers added non-traditional ingredients like sawdust or hay to the bread dough.
These ingredients were used as extenders to make the bread loaves larger without using more grain, which was in short supply. This practice helped to fill the stomachs of people even when the grain itself was not sufficiently available or nourishing due to a lack of proper ripening caused by inadequate summer sunshine.