Kate San's study, published in Nature, shows that the ancients lined up the pyramids with two stars whose alignment was only true around 4,500 years ago,which makes it possible to improve the margin of error in the archaeological chronology of ancient Egypt, from plus or minus 100 years to only five years, which makes it possible to pinpoint what people probably think was the start of construction of Khufu's Great Pyramid at Giza to around the year 2467 BC.

A) which makes it possible to improve the margin of error in the archaeological chronology of ancient Egypt, from plus or minus 100 years to only five years, which makes it possible to pinpoint what people probably think was the start

B) which makes it impossible to stick to the margin of error in the archaeological chronology of ancient Egypt, which was plus or minus 100 years in favor of one which is only five years, pinpointing the probable start

C) suggesting that the margin of error for the archaeological chronology of ancient Egypt is no longer plus or minus 100 years, but rather only five years, which suggests the possibility of pinpointing the probable start

D) making improvements in the margin of error in the archaeological chronology of ancient Egypt, from plus or minus 100 years to only five years, pinpointing the probable start

E) making it possible to improve the margin of error in the archaeological chronology of ancient Egypt, from plus or minus 100 years to only five years, pinpointing the probable start.

[spoiler]OA later
I am stuck between D and E.
I am unable to understand the meaning of it ( making it possible) in E, somebody please explain
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