The mode of craft production favored the growth of self-governing and ideologically egalitarian craft guilds everywhere in the Middle Eastern City. These were essentially professional associations that provided for the mutual aid and protection standards. The growth of independent guilds was furthered by the fact that surplus was not a result of domestic craft production but resulted primarily from international trading; the government left working people to govern themselves, much as shepherds of tribal confederacies were left alone by their leaders. ……
题目如下:Why does the author mention "surplus was not a result of domestic craft production but resulted primarily from international trading"?
A support the claim that the mode of production made possible by the craft guilds was very good for trade.
B contrast the economic base of the city government will that of the tribal.
C Provide a reason why the government allowed the guilds to be self-controlled.
D suggest that the government was missing out on valuable opputunity.