A. The majority of them are composed of red sandstone.
B. They must have reached their present location over 1,500 years ago.
C. They were carried byicebergs to their present location.
D. Most of them were carried to their present location during a warm period inEarths climatic history.
E. They are unlikely to have been carried to their present location during theLittle Ice Age.
21.2. In the final paragraph of the passage ,the author is concerned primarily with
A. answering a question about Earths climatic history
B. pointing out a potential flaw in Bonds hypothesis
C. suggesting a new focus for the study of ocean sediments
D. tracing the general history of Earths climate
E. discussing possibleimplications of Bonds hypothesis
21.3. According to the passage, Bond hypothesized that whichof the following circumstances would allow red-stained sediment grains to reachmore southerly latitudes?
A. Warm waters being pulled northward from the GulfStream
B. Climatic conditions causing icebergs to melt relatively quickly
C. Icebergs containing a higher proportion of iron oxide than usual 31
D. The formation of more icebergs than usual in the far north
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