听力原文:An index is a statistical composite representing the value of all stocks in a certain market segment.It's presented as one number so investors can track trends in that segment.The broader the index, the more representative it is of the entire stock market.The Dow Jones Industrial is an average of 30 of the most widely held stocks.The S&P 500 Index combines the prices of 500 widely held stocks chosen by Standard and Poor's.The Russell 2000 includes 2000 small-company stocks; the Wilshire 5000 includes both small-and large-company stocks and is weighted to represent all U.S.-headquartered securities.
Which of the following index represents small-company stocks?