Definition: In this task, you're given a question, along with a context passage which has extra information available on certain terms mentioned in it, i.e., the proper nouns in the passage. Your job is to determine whether information from more than one term is needed to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: What were the main groups involved in the event that resulted in the sacking of Constantinople in 1204? Passage:Papal calls for renewed holy war at the end of the twelfth century inspired not only the disastrous Fourth Crusade that sacked Constantinople in 1204, but also a series of simultaneous "Northern Crusades" that are less fully covered in English-language popular history, but which were more successful in the long run. Before the crusades, the region of Livonia was a mixed outpost, a pagan society where merchants from the Hanseatic League encountered merchants of Novgorod, and where Germanic, Scandinavian, and Russian trade, culture, and cults all mingled. The specific ethnic groups that intermingled and traded with the Germans, Danish, Swedish, and Russians here included the Wends, who were merchants from Lübeck, the Estonians, the Karelians, the Kuronians, the Lettgallians, the Semgallians (sometimes known as the Letts), the Livonians and the Lithuanians. The Western merchants would trade silver, textiles, and other luxury goods for furs, beeswax, honey, leather, dried fish, and amber. Livonia had been an especially promising location in terms of resources, and Arnold of Lübeck, in his Chronicle of the Slavs wrote that the land was "abundant in many riches" and was "fertile in fields, plentiful in pastures, irrigated by rivers", and "also sufficiently rich in fish and forested with trees".


b