单项选择题
A.Hardly he has found B.No sooner had he found C.Not until did he find D.When he found
A.a bad impact on other industries B.a change of tourists'customs C.overcrowdedness of places of interest D.pressure on traffic
A.It is extremely important to develop tourism. B.Building roads and hotels is essential. C.Support facilities are highly necessary. D.Planning is of great importance to tourism.