That the Leaning Tower of Pisa no longer leans quite so much after a ￡20 million project to save it has proved to be a great success.The tower, which was on the edge of collapse, has been straightened by 18 inches, returning it to its 1838 position.

“It has straightened a little bit more than we expected, but very little helps, ”said Prof.John Burland, the only British member of the rescue committee.“The tower is still very slightly moving towards being upright. ”
The tower, which has been leaning almost since building work first began in 1173, was closed to the public in 1990 because of safety fears.The 183foot tower was nearly 15 feet off vertical and its structure was found to have been weakened by centuries of strain(作用力).
Prof.Burland said it could have collapsed “at any moment”．However, it took nine years of quarreling before any work was done.The last attempt at straightening the tower was carried out. Concrete was poured into the foundations, but the result was that the tower sank further into the soil.
The straightening work involved digging out around 70 tonnes of earth from the northern side of the tower, causing it to sink on that side.Before the digging started, the tower was fixed with steel ropes and 600 tonnes of lead weights.
However, halfway through the project, concerns at the ugliness of the weights led to their removal and the tower leaned greatly.The weights were hurriedly reattached. In one night, the tower moved more than it had averaged in an entire year.The tower's stonework has also been restored.
The Italian government stepped in after a tower collapsed in Pavia in 1989, killing four people.Experts suddenly realized that the tower at Pisa, which was similarly built and on the same sort of earth, could do the same.
What would be the best title for the passage?

A．The Building of the Leaning Tower of Pisa

B．Saving the Leaning Tower of Pisa

C．The Collapse of the Leaning Tower of Pisa

D．The History of the Leaning Tower of Pisa

According to the passage, the Leaning Tower of Pisa_________________.

A．closed for the straightening work in 1990

B．began to lean more than 800 years ago

C．has a history of more than 1, 000 years

D．has become vertical

What drove the Italian government to save the Leaning Tower of Pisa?

A．The development of new technology.

B．The advice of Prof. John Burland.

C．The expectation of the rescue committee.

D．The collapse of a tower in Pavia.

What most probably played the most important part in straightening the tower?

A．The lead weights fixed to the tower.

B．Restoring the stonework.

C．Pouring concrete into the foundations.

D．Digging earth from the southern side of the tower.