Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
Not so long ago, prediction markets (市场预测) were being considered as a fantastic new way to forecast everything from the completion date of a vital project to a firm's annual sales. But although they have spread beyond early-adopting companies in the technology industry, they have still not become mainstream management tools. Even crazy advocates admit much remains to be done to convince doubtful managers of their value. "It's still a pretty blessing business, " says Leslie Fine of CrowdCast, one of the firms that provide trading platforms for companies keen to pool the collective wisdom of their employees.
Prediction markets work by giving people virtual trading accounts that allow them to buy and sell "shares" that correspond to a particular outcome. Shares in an outcome that is considered more likely to occur then trade at a higher price than those that represent a less likely outcome. This provides a way to approach the tacit (默许的) knowledge that exists in companies, especially ones that have many different divisions or offices.
Koch Industries, an American company in a range of businesses including chemicals, fertilizers and commodity trading, has been running prediction markets for the past nine months involving about 200 of its staff from different areas. The group, which has revenues of some $100 billion, has launched contracts on, among other things, the future prices of raw materials used in its chemicals division and the likelihood of bank nationalizations. Koch says the results so far have been pretty accurate compared to actual outcomes, but stresses that markets are complementary to other forecasting techniques, not a substitute for them.
A big obstacle facing managers using prediction markets is getting enough people to keep trading after the novelty has worn off. Many firms use gaming-style. leader boards to encourage internal competition, or offer modest prizes to the most successful traders. Lloyds TSB, a bank, launched a market in which participants identify the best new ideas by trading in a currency called Bank Beanz, which can then be exchanged for cash--a scheme the bank's head of innovation calls "an exceptional motivator".
Another reason prediction markets failed is that employees cannot see how the results are used, so they lose interest. Wells Fargo, a big bank that has been running internal markets for over a year to identify ways to improve service to some corporate customers, says its most effective tests took place in areas where managers could do something with their findings, making staff feel that trading was worthwhile.
Bosses may also be wary of relying on the judgments of non-experts. Yet many pilot projects run so far have shown that junior staff can often be surprisingly good forecasters. Perhaps the best way to find out when prediction markets will finally take off is to ask your employees--using a prediction market.
What does the author tell us about the prediction market in the passage？

A. It now has become a major management way for most companies.
B. The advocates are too optimistic about prediction market.
C. It is a way to know firms' own covert knowledge.
D. It works by giving traders an actual trading accounts.