[LR][PT22-S2-Q19]meteorite impact

umcwayneUID：2674663

請問隕石坑和磁極&磁極形成的時間&滅絕有什麼關係呢? 謝謝

Professor Robinson: A large meteorite impact crater in a certain region was thought to be the clue to explaining the mass extinction of plant and animal species that occurred at the end of the Mesozoic era. However, the crystalline structure of rocks recovered at the site indicates that the impact that formed this crater was not the culprit. When molten rocks crystallize, they display the polarity of Earth's magnetic field at that time. But the recrystallized rocks recovered at the site display normal magnetic polarity, even though Earth's magnetic field was reversed at the time of the mass extinction.
Each of the following is an assumption on which Professor Robinson's argument depends EXCEPT:

(A)The crater indicates an impact of more than sufficient size to have caused the mass extinction. (OA)

(B)The recovered rocks recrystallized shortly after they melted.

(C)No other event caused the rocks to melt after the impact that formed the crater.

(D)The recovered rocks melted as a result of the impact that formed the crater.

(E)The mass extinction would have occurred soon after the impact that supposedly caused it.

duijinxiaoziUID：2585955

1# umcwayne

陨石落下---》产生隕石坑-----》 molten rocks crystallize ---》记录当时地球的磁極（是normal magnetic polarity，与“Earth's magnetic field was reversed at the time of the mass extinction.”不符）

umcwayneUID：2674663

謝謝版主

lily88888UID：2828533

OA: official answer?

umcwayneUID：2674663

yes