A company has been using the FIFO cost method of inventory valuation since it was started 10 years ago. Its 2018 ending inventory was $180,000, but it would have been $130,000 if LIFO had been used. Thus, if LIFO had been used, this company's income before taxes would have been

a.$50,000 less in 2018.

b.$50,000 greater in 2018.

c.$50,000 greater over the 10-year period.

d.$50,000 less over the 10-year period.