For the years 2010 through 2014 (inclusive) mary, a best-selling author, has been involved in operating an antique store. in 2010, 2011 and 2012 her revenue exceeded the expenses from the activity. in 2013 and 2014, the antique store generated a loss. which statement is correct? a) the activity is a business. the irs cannot prove it is a hobby. b) the activity is a hobby. mary cannot prove it is a business. c) the activity is presumed to be a business. however, the irs may prove it is a hobby. d) the activity is presumed to be a hobby. however, mary may prove it is a business.