how did the rivalry between the habsburgs and hohenzollerns affect central europe

Answer 1

This feels like a homework question, so I don't want to give you the complete answer here. The largest effect is the boundaries of modern Germany. The Habsburgs ruled Austria, which is a German-speaking country, and was considered part of the region of Germany until 1871. In that year the Hohenzollern rulers of Prussia created the modern country of Germany, which combined a lot of different German-speaking countries. But because of their rivalry with the Habsburgs, Austria did not join this unified Germany.

That's probably the most significant consequence of the rivalry. There were a number of wars and diplomatic incidents throughout the 18th and 19th centuries that led up to this. Their rivalry also had consequences for Poland, but I don't know if your class considers Poland part of Central Europe. I hope that this is a good place to begin!