A small local firm is about to m

A small local firm is about to move to larger premises. The Anscot Electrical Goods Company has been very successful (31) it was formed four years ago (32) Tony Scott. Until now the company(33) from the ground floor of an old factory in Bolton, but it recently bought a unit in a new industrial area.
(34) most of the company's business is (35) firms in the north of England, (36) has recently signed contracts to supply a major retailer in Sweden.
“The (37) of customers we serve is growing all (38) times, "says Tony Scott, "so the number of people we employ has also grown over the four years we've (39) in business . I don't have (40) doubts that as soon as we are settled in the new building we will need to employ still more staff. "
回答第（37）空
A、amount
B、deal
C、number
【正确答案】：C