L flew from Chicago to Miami primarily for a business meeting. The meeting lasted three days, so she stayed in Miami for two additional days to enjoy the sunshine and visit. With respect to the plane fare for the trip, L should

a. prorate the plane fare based on time devoted to business and personal activities and deduct the business portion.

b. divide the plane fare equally between business and personal activities and deduct the business portion.

c. deduct the entire plane fare.

d. deduct none of the plane fare.

e. none of the above.