A.1+1/2+1/3+1/4

B.1+1/2+1/(3×2)+1/(4×3×2)

C.1+1/2+1/3+1/4+1/5

D.1+1/2+1/(3×2)+1/(4×3×2)+1/(5×4×3×2)

解析:由算法框图依次可得,输入N=4,

T=1,S=1,k=2,2<4;

T=1/2,S=1+1/2,k=3,3<4;

T=1/(3×2),S=1+1/2+1/(3×2),k=4,4=4;

T=1/(4×3×2),S=1+1/2+1/(3×2)+1/(4×3×2),k=5,5>4;

输出S=1+1/2+1/(3×2)+1/(4×3×2).

答案:B

7.循环结构的算法框图如图所示,下列说法中正确的是　　　　　.

①A是循环变量初始化,循环将要开始;

②B为循环体;

③C是判断是否继续循环的条件;

④A可以省略不写.

答案:①②③