Definition: In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: The Avars ruled over a basin in 560, what current country is that area located in? Passage:Since about 560, the Avars had ruled over large parts of the Pannonian Basin and Carantania southeast of Francia, though in the last decades, the Avar Khaganate had to deal with Bulgarian and Croat incursions. To secure the frontier of his empire and the traffic on the trade routes to the east, Charlemagne allied with Khan Krum of Bulgaria and the Croatian duke Vojnomir, and from 791 launched several campaigns against the Avars, where he, according to the Vita Karoli Magni, encountered only modest opposition. In 796 Carolingian forces under Charlemagne's son Pepin of Italy destroyed the main Avar fortress called the Ring of the Avars and made the Khagan a Frankish vassal, while the remaining Avars retreated behind the Tisza River. The victory is perpetuated by the poem De Pippini regis Victoria Avarica. 


b