题目内容：

    Archaeologists used DNA taken from a broken clay pipe stem found in Maryland to build a picture of an enslaved woman who died around 200 years ago and had origins in modern-day Sierra Leone. One researcher called the work “a mind-blower.”

“In this particular context, and from that time period, I think it's a first,” team member Hannes Schroeder told The Washington Post. “To be able to get DNA from an object like a pipe stem is quite exciting. Also it is exciting for descendant(后裔) communities... Through this technology, they're able to make a connection not only to the site but potentially back to Africa.”

The pipe stem was found at the Belvoir plantation in Crownsville, Maryland, where enslaved people lived until 1864 and where a likely slave cemetery was recently found. DNA taken from the pipe linked back to a woman either directly from or descended from the Mende people, who lived in west Africa, in an area now part of Sierra.

Julie Schablitsky, the chief archaeologist with the Maryland state highway administration, told The Post the discovery, based on saliva(唾液) absorbed into the clay pipe, was a “mind-blower”. She also said records show the existence of a slave trade route Sierra Leone to Annapolis, plied(定期往来) by British and American ships. "As soon as people stepped on those slave ships in Africa," she said, “whether they were from Benin or whether they were from Sierra Leone, wherever they were from, that identity was lost. Their humanity is stripped from. Who they are as a people has gone.”

The new analysis is part of ongoing research around Belvoir that has given descendants of the people enslaved there new insight into the lives of their ancestors. Speaking to The Post, Nancy Daniels, a genealogist from Laurel, Maryland, who thinks she is a descendant of enslaved families from Belvoir but was not linked to the research on the pipe, called the discovery “overwhelming.” “I'm sitting here about ready to cry,” she said. “I'm sorry. I'm so happy ... Thank God for the DNA.”

This year, events and ceremonies are being held to mark the 400th anniversary of the arrival of the first enslaved people in America, at Jamestown, Virginia, in 1619. Slavery was effectively abandoned in the US on 1 January 1863, with the issue by Abraham Lincoln of the Emancipation Proclamation. It formally ended in December 1865, after the civil war, with the approval of the 13th amendment(修正案).

1.What does the phrase “a mind-blower” in paragraphs 1 and 4 refer to?

A.A surprise B.A confusion

C.An excitement D.A fascination

2.According to Hannes Schroeder, the pipe stem was of great significance because________.

A.it was the first direct evidence that slaves living in Maryland were originally from Africa.

B.it helped the archaeologists to draw a portrait of the enslaved woman.

C.it might contribute to identifying the birthplace of the descendant communities.

D.it contained genic clues to the ancestral background of its owner.

3.What can be inferred from the passage?

A.The owner of the pipe once lived in what is now an area in west Africa.

B.The history of slavery in America is an ongoing topic of concern.

C.African slaves lost their identities when they arrived at the Belvoir plantation.

D.Nancy Daniels, a genealogist was sorry for not being involved in the research.

4.Which of the following is the best title for the passage?

A.DNA from an old pipe throws lights on the origins of the enslaved

B.A new research reveals the origins of enslaved African woman

C.The descendants of enslaved people seek their identities

D.DNA contributes to the breakthrough of a new research