Henry: An average American car driver drives a thousand miles per month. If all American car drivers drove only five miles less daily, their monthly mileage would reduce by 15 percent. Five miles is ten thousand steps, the amount of daily walking recommended by doctors for good health. Therefore, if the government could persuade car drivers to drive five miles less daily and walk that distance instead, the total transport-related carbon emissions in the United States would reduce by 15 percent. Bill: Cars are responsible for 30 percent of all transport-related carbon emissions in the United States.

Bill's response to Henry proceeds by

A refuting an assumption on which Henry's argument relies
B discrediting Henry's argument by giving of erroneous information
C arguing that the benefit of Henry's hypothetical measure might also be achieved in another way
D citing seemingly irrefutable evidence that contradicts one of the stated premises on which Henry's argument depends
E providing additional information in support of Henry's argument