A、The northern part. B、The southern part. C、The western part. D、The eastern part. A此题考的是细节问题，在文章第一段就可以听到是北端开始融化。

The Larsen B shelf was no ordinary piece of ice because it covered more than 3,000 square kilometres and was 200 metres thick. Scientists say they have discovered the ice relatively intact for at least 10,000 years or since the last ice age. Now that it has broken up it is causing changes in currents and species in the area.But that is not all. Robert Gilbert is a geography professor with Queen’s University in Ontario. He is the only Canadian in the international team looking at the ice shelf. "As the ice shelves are disintegrating, the glaciers that are feeding them from the land are surging forward, and they are no longer held back by the ice shelf." Gilbert says the glaciers are pushing ice in the form of icebergs into the sea.As they melt, he says, there will be an effect on sea level that will be felt around the world.He says now scientists are watching to see if the most southern part of the Larsen ice shelf is going to break up. It is in the most protected and the coldest part of Antarctica.Gilbert is now on his way to Greenland to see what changes are happening with the ice there.