单选题：根据下列材料，回答题The Body Thieves　　In the early nineteenth century

根据下列材料，回答题 The Body Thieves 　　In the early nineteenth century in Britain，many improvements were being made in the world of medicine．Doctors and Surgeons were becoming more knowledgeable about the human body．Illnesses that had been fatal a few years before were now curable．However，Surgeons had one problem．They needed dead bodies to cut up，or dissect(解剖)．This was the only way that they could learn about the flesh and bones inside the body， and the only way to teach new surgeons to carry out operations．
　　The job of finding these dead bodies was carded out by an unpleasant group of people called“body snatchers”．They went into graveyards(墓地)at night and，using wooden shovels to make less noise。dug up any recently buried bodies．Then they took the bodies to the medical schools and sold them．A body could be sold for between￡5 and l0，which was a lot of money at that time．The doctors who paid the body snatchers had all agreement with them—they never asked any questions．They did not desire to know where the bodies came from，as long as they kept arriving．
　　The most famous of these body snatchers were two men from Edinburgh called William　Burke and William Hare． Burke and Hare were different because they did not just dig Up bodies　from graveyards．They got greedy and thought of all easier way to find bodies. Instead of digging them up．they killed the poorer guests in Hare’s small hotel. Dr.Knox，the respected surgeon they worked for．never asked why all the bodies they brought him had been strangled(勒死)．
　　For many years Burke and Hare were not caught because，unsurprisingly，the bodies of their victims were never found by the police．They were eventually arrested and put on trial in 1829．The judge showed mercy to Hare and he was released but Burke Was found guilty and his punishment was to be hanged．Appropriately，his body Was given to the medical school and he ended up on the dissecting table，just like his victims．In one small way，Justice was done.
　　Now, over 150 years later，surgeons do not need the help of criminals to learn their skills．However．the science of surgery could not have developed without their rather gruesome(令人毛骨悚然的)help．

The problem facing British surgeons in the early 19th century was that______· A．some illnesses remained incurable
B．few people were willing to work as surgeons
C．medical expenses were too high
D．dead bodies were not easily available