In the international market, goods on sale coming from different countries and suppliers are always facing keen competition. Under such circumstances, they will try everything possible to familiarize themselves with the market conditions. In making investigations, we ought to get information about what similar items the competitors are offering on the market, what prices they are quoting (报价), what features their products have, who are their regular customers, etc. Then, how can we obtain such information？ There are many channels that we can make use of in doing this sort of work. The commercial counselor's offices of our embassies stationed abroad can help us in making market investigations. Nowadays, our import and export corporations send their trade groups abroad every now and then. One of their purposes is to make market surveys on the spot.
Certainly, face-to-face talks with foreign businessmen are also important channels to get market information. The Chinese Export Commodities Fairs and some other fairs of similar nature as well as visits of foreign businessmen provide us with such opportunities. Of course, there are some other ways of making market investigations.
In making market investigation, one should ______.

A. get enough information concerned
B. advertise his products
C. produce high quality goods
D. none of the above