题目

New kinds of tourismPeople are travelling more than ever before.The World Tourism Organisation says that by 2020 the number of international travellers will be more than 1.6 billion people per year.【1】 Here are four different kinds of tourism that have appeared recently.Medical tourism can be for a lot of things，from operations to visits to the dentist.【2】 A few of the popular countries offering medical tourism are India，Cuba，Thailand and Jordan.Nearly all tourists eat in restaurants，and dining is one of the top three tourist activities.But if you were in a country famous for i提出有机化学概念，使有机化学逐渐发展成为化学的一个重要分支的科学家是（　　） A、维勒B、贝采利乌斯C、李比希D、科里