A．duck
B．duty
C．dust
D．dump

A．the Wall Street
B．the stock exchange
C．the stock
D．the stockholder and stockbroker

A．The stockholder can sell his stock to anywhere at anytime.
B．There were no stock exchange in England in the 1700's.
C．The price of stock is not stable.
D．The stockbrokers do the transaction without charging for the stockholders.