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: How long did the Siege of Boston last? Passage:The Battle of Lexington and Concord was the first conflict in the American Revolutionary War. On April 19, 1775, a force of British Army regulars marched from Boston to Concord to capture a cache of arms that was reportedly stored in the town. Forewarned by Samuel Prescott (who had received the news from Paul Revere), the colonists mustered in opposition. Following an early-morning skirmish at Lexington, where the first shots of the battle were fired, the British expedition under the command of Lt. Col. Francis Smith advanced to Concord. There, colonists from Concord and surrounding towns (notably a highly drilled company from Acton led by Isaac Davis) repulsed a British detachment at the Old North Bridge and forced the British troops to retreat. Subsequently, militia arriving from across the region harried the British troops on their return to Boston, culminating in the Siege of Boston and the outbreak of the war.

Output:
b