Suppose Erie Textiles can dispose of its waste "for free" by dumping it into a nearby river. While the firm benefits from dumping waste into the river, the waste reduces fish and bird reproduction. This causes damage to local fishermen and bird watchers. At a cost, Erie Textiles can filter out the toxins, in which case local fishermen and bird watchers will not suffer any damage. The relevant gains and losses (in thousands of dollars) for the three parties are listed below. WithFilterWithoutFilterGains to Erie$200$400Fisherman$180$50Bird Watchers$130$25The cost (in thousands of dollars) of the filter to Erie Textiles is ________, and the net benefit (in thousands of dollars) of the filter to the fishermen and bird watchers is ________.

A. $200; $75
B. $200; $235
C. $310; $200
D. $400; $310

Answer: B