Final answer:
The Holy Roman Empire was fragmented into independent states after the Thirty Years' War with the Peace of Westphalia in 1648, which established the sovereignty of nearly one thousand entities within the empire. so, option b is the correct answer.
Step-by-step explanation:
The Holy Roman Empire underwent significant change at the end of the Thirty Years' War. The conflict, which lasted from 1618 to 1648, was characterized by religious and political struggles primarily on German lands. With the Peace of Westphalia in 1648, the Holy Roman Empire was effectively fragmented into independent states. This peace agreement recognized the sovereignty of each of the entities within the Holy Roman Empire, numbering nearly one thousand, and thus established their independence.
The outcome of the war and resultant treaty reinforced the notion that Germany remained more an idea than a unified nation until later in the 19th century with the unification of Germany. The Thirty Years' War and the Peace of Westphalia played a crucial role in shaping the future of Europe.