完形填空,从A、B、C三个选项中选择正确答案

完形填空,从A、B、C三个选项中选择正确答案
Some people know little about the topic under (23).Sometimes they do not even know what the host is talking about.So the host has to (24) the caller what the show is about.Usually the caller will (25) a few questions which express his hope and show his ignorance.Then the host has to answer and explain——how silly this is!It (26) a lot of time.
It seems that some people phone the hotlines in fun.They (27) want to let the listeners hear them.They don't care what the topic is and (28) they themselves are interested in the topic or not.How silly they appear to be!
It's (29) for radio stations to improve the hotline programs.If a caller doesn't know what is going (30),the operator should not let the caller take part in it.
23.A.discussion B.meeting C.party
24.A.make B.teach C.tell
25.A.ask B.solve C.write
26.A.saves B.wastes C.sees
27.A.already B.hardly C.just
28.A.when B.what C.necessary
29.A.impossible B.interesting C.necessary
30.A.no B.off C.away
28.C.whether