下面程序的输出是 ______。main(){int x=3 ,y=6,a=0;, while(x++!=(y=1)) { a+=1; if(y＜x) break; } printf("x=%d, y=%d, a=%d\n, x, y, a);}

A．x=4,y=4,a=1

B．x=5,y=5,a=1

C．x=5,y=4,a=3

D．x=5,y=4,a=1