Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
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Question: Electronic book publishing has many of the same risks and opportunities as electronic music publishing. By delivering text direct to the user's computer screen, the e-book could cut down costs, and allow creators to deal directly with their audience, bypassing traditional publishers and readers. But it also raises the possibility of mass piracy . Phil Rance, founder and managing director of Online Originals, a London-based e-book publisher, sums it up. "No one wants Napster to happen to books." Indeed, the most popular MP3 have put the frighteners on an industry that generally operates some way behind the "bleeding edge". The Mata Group, a leading US-based market researcher, says publishers are far too concerned about protecting their rights, "We believe all the recent legal control over Napster is like putting a finger in a river that is already overflowing. Publishers need to deal with reality and come up with new ways to develop wide electronic distribution , asking the question: 'How can we use the certainty of wide distribution to our advantage?'" At the moment, most publishers would like to limit the use of e-books to the person who bought them, or to the computer used to download them. If that can be done, e-books become just an extra income stream in a publishing industry that would continue to operate the way it does today, according to Terry Robinson, business manager for Adobe's e-paper group. "If you've cracked digital rights aspect, you've cracked the market," he says. Robert Nichols, Books Director at BOL agrees, "Rights management is absolutely important. Publishers just say that 'until copyright is secure, we're not going to talk'."

Answer: What do publishers care most about e-books?

Question: You have been badly injured in a car accident. It is necessary to give you a blood transfusion because you lost a great deal of blood in the accident. However, special care must be taken in selecting new blood for you. If the blood is too different from your own, the transfusion could kill you. There are four basic types of blood; A, B, AB, and O. A simple test can make sure of a person's blood type. Everybody is born with one of these four types of blood. Blood type, like hair color1 and height, is received from parents. The four groups must be transfused carefully. A and B cannot be mixed. A and B cannot receive AB, but AB may receive A or B. O can give to any other group; therefore, it is often called the universal donor . For the opposite reason, AB is sometimes called the universal recipient . However, because so many reactions can happen in transfusions , patients usually receive only salt of plasma (liquid part of blood) until their blood can be matched as exactly as possible in the blood bank of a hospital. In this way, it is possible to prevent the transfusion from any bad reactions.

Answer: People with type A blood can receive type .

Question: The restless legs syndrome is characterized by an unpleasant sensation in the legs which causes an imperative need to move the legs and is therefore considered to be a disorder of movement. When it appears before going to sleep, it may interfere with falling asleep and lead to a sleep-deficit. It is a clinical condition with a satisfactory treatment, and improvement of the associated sleep disorder. The etiology is unknown, sometimes it is familial. The syndrome is increasingly often diagnosed, particularly in association with iron deficiency, during pregnancy, in chronic renal failure and in patients with peripheral neuropathy. Polysomnography is not necessary, unless one suspects an associated disorder of periodic leg movements. Treatment is by dopaminergic, opiate, benzodiazepine, anticonvulsant drugs or clonidine.

Answer:
Which deficiency is the cause of restless leg syndrome?