Q: This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Passage: The Napoleonic Wars were the cause of the final dissolution of the Holy Roman Empire, and ultimately the cause for the quest for a German nation state in 19th-century German nationalism. After the Congress of Vienna, Austria and Prussia emerged as two competitors. Austria, trying to remain the dominant power in Central Europe, led the way in the terms of the Congress of Vienna. The Congress of Vienna was essentially conservative, assuring that little would change in Europe and preventing Germany from uniting. These terms came to a sudden halt following the Revolutions of 1848 and the Crimean War in 1856, paving the way for German unification in the 1860s. By the 1820s, large numbers of Jewish German women had intermarried with Christian German men and had converted to Christianity. Jewish German Eduard Lasker was a prominent German nationalist figure who promoted the unification of Germany in the mid-19th century. Question: What two countries emerged as competitors after the Congress of Vienna?
A:
Austria and Prussia