Sometimes advertisements make________ possible for companies to sell the customers________ money cannot buy..

A． /; that

B．it; what

C．that; which

D．/; whose

曲线（）

A．仅有水平渐近线

B．既有水平渐近线又有铅直渐近线

C．仅有铅直渐近线

D．既无水平渐近线又无铅直渐近线