President Hu Jintao said economic growth is the basis for strengthening defense capability, which is ____,

an important indicator of overall national strength. [ ]

A. in turn

B. in return

C. on a large scale

D. in a row

m个产地、n个销地的产销平衡的运输问题，在用表上作业法求解时，基格的个数一定是（）。

A.（m+n）个

B.（m+n-1）个

C.（m+n+1）个

D.不一定