Final answer:
The Frankfurt Parliament was thwarted in their efforts by monarchs who reasserted their power, resulting in the return to the pre-revolutionary order and a sense of defeat among the liberals and nationalists.
Step-by-step explanation:
The Frankfurt Parliament's reaction to the challenges posed by the Industrial Code and the broader context of the Industrial Revolution was largely ineffective. During the period of revolutionary upheaval in Europe, the Frankfurt Parliament consisted mainly of impassioned and educated individuals like lawyers, who unfortunately lacked direct links to the majority of the German population. While they were absorbed in discussions over national identity and liberal constitutions, monarchs were quietly regaining control over their armies and consolidating support, leading to the reassertion of monarchical power in German kingdoms, Italy, and Austria. Consequently, the political and idealistic goals of the Frankfurt Parliament did not translate into widespread practical changes, and the initial revolutionary changes were largely reversed, reinstating the previous order and creating disillusionment among liberals and nationalists.