单选题
The "white chalk cliffs of Dover" are mentioned in line 14 of the passage to
A、
( show where the plankton sediment first began to build up
B、
( provide an example of a plankton buildup that scientists cannot explain
C、
( provide all example of the buildup of plankton sediment
D、
( indicate the largest single plankton buildup on Earth
【正确答案】
C
【答案解析】
提交答案
关闭