【单选题】The words in brackets in the sentence below have at least two meanings. Look at how they are used and choose the correct meaning. Many companies today are operating on extremely tight (margins ).
A.
the column of space down the side of a page
B.
the difference in the number of points between the winners and the losers of a sports event or competition
C.
the difference between what it costs to buy or produce something and its selling price