We might safely infer that local merchants and small firms do not often use national television advertising simply because_____

We might safely infer that local merchants and small firms do not often use national television advertising simply because_____

A.they can’t afford the huge costs

B.it will not bring them the profit in proportion to their advertising expense

C.it does not cover the whole market

D.radio advertising can reach to a wider audience

正确答案是B