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: Which river is longer, the river that drains the central portion of the county, or the river that drains the western portion? Passage:The damming of the Hackensack River and a tributary, the Pascack Brook, produced three reservoirs in the county, Woodcliff Lake Reservoir (which impounds one billion gallons of water), Lake Tappan (3.5 billion gallons), and Oradell Reservoir, which allows United Water to provide drinking water to 750,000 residents of northern New Jersey, mostly in Bergen and Hudson counties. The Hackensack River drains the eastern portion of the county through the New Jersey Meadowlands, a wetlands area in the southern portion of the county. The central portion is drained by the Saddle River and the western portion is drained by the Ramapo River. Both of these are tributaries of the Passaic River, which forms a section of the southwestern border of the county.


a