سلام دوستان این یه قسمت از متن ریدینگ power prep هست که با یکی از سوالات inference گذاشتم اینجا ...میشه به من بگید جواب این سوال رو چطور باید infer کنیم؟

Bond hypothesized that the alternating cycles might be evidence of changes in ocean-water circulation and therefore in Earth’s climate. He knew that the sources of the red-stained grains were generally closer to the North Pole than were the places yielding a high proportion of “clean” grains. At certain times, apparently, more icebergs from the Arctic Ocean in the far north were traveling south well into the North Atlantic before melting and shedding their sediment.

ترجمش این میشه:
Bone میدونسته که منبع red sediment نزدیک به قطب شمال بوده. در زمان های مشخصی Ice berg های بیشتری از Arctic Ocean (که همون north میشه) به سمت south حرکت میکنه و میریزه به North Atlantic ...
حالا پرسیده که Bone بر اساس چه شرایطی و چطوری فرض کرده که red sediment به سمت جنوب میره؟
14. According to the passage, Bond hypothesized that which of the following circumstances would allow red-stained sediment grains to reach more southerly latitudes?

A. Warm waters being pulled northward from the Gulf Stream
B. Climatic conditions causing icebergs to melt relatively quickly
C. Icebergs containing a higher proportion of iron oxide than usual
D. The formation of more icebergs than usual in the far north
E. The presence of cold surface waters in the North Atlantic

جواب میشه گزینه E ....سوال من اینه که Cold surface water رو باید از همون حرکت ice berg بفهمیم؟