若有定义:
float x=1.5;
int a=1,b=3,c=2;
则正确的switch语句是______。
A
switch(a+b)
{ case 1: printf("*\n");
case 2+1: printf("**\n"); }
B
switch((int)x);
{ case 1: printf("*\n");
case 2: printf("**\n"); }
C
switch(x)
{ case 1.0: printf("*\n");
case 2.0: printf("**\n"); }
D
switch(a+b)
{ case 1: printf("*\n");
case c: printf("**\n"); }