I can't say which wine is best---it's a(n)_______of personal taste.

A．affair

B．matter

C．event

D．variety

下列程序的输出结果是
int t(intx,inty,int cp,int dp)
cp=x*x+y*y；
dp=x*x-y*y；

main()
int, a=4,b=3,c=5,d=6;
t(a,b,c,d);
printf("%d %d\\n",c,d);