February 24,2008 saw thieves break into the showroom of an Italian jeweler liked by Holly

February 24,2008 saw thieves break into the showroom of an Italian jeweler liked by Hollywood stars and stole things worth up to 10 million dollars while its owners were in Los Angeles hosting a party to celebrate the Oscars．
The robbery，which took place at the Damiani showroom in Milan’s fashion district that morning，was pared later with the“perfect scenes”in films such as Ocean’s Eleven and The Italian Job．
The thieves had spent more than a month digging a tunnel from a disused cellar(地下室)in a building joined to the showroom．The digging had been heard for weeks but was thought to be part of continuing building works next door. The four thieves，dressed in balaclavas，sunglasses and fake uniforms of the Guards, used an inside stair to reach the first floor，thus avoiding alarms(警报器) and video cameras．
The showroom had been opened for a private viewing and there were five employees inside，including a cleaning lady and a member of the staff，as well as the manager. The thieves said they were there to check the accounts(账目)，then knocked down the staff，tied them up with ropes，covered their mouths with tape and locked them in the washroom. They then helped themselves to jewelry and left the way they had e．
The entire operation had taken little more than 40 minutes．The employees managed to free themselves and raise the alarm，but by then the thieves were long gone．The police said that they were looking into whether the robbers had“inside assistance”that had helped them to avoid the alarms and cameras．
45．Which of the following is the best title of this passage?
A．A perfect robbery        B．10 million of Jewelry Stolen
C．The Italian Thieves       D．An Italian Jeweler
46．Why didn’t the thieves appear in the cameras? Perhaps because    ．
A．there was something wrong with the cameras then
B．the thieves entered the showroom through an inside stair
C．the employees were too frightened to open the cameras then
D．the cameras didn’t work with the uniforms of the guards
47．Which of the following is true according to the passage?
A．The Italian jeweler was popular with some famous American film stars．
B．The thieves went into a disused tunnel into the showroom．
C．When the robbery took place，there was no one in the showroom．
D．One of the jeweler employees must have helped the robbery secretly．
48．We can learn from the passage that    
A．The items were so dear that no one could afford to buy one．
B．The thieves left the showroom from where they came into it．
C．The most valuable jewels survived the robbery．
D．The jeweler had to close down because of the showroom robbery．45—48   ABAB