C
分析:将原式化为

=

的形式,再将数值代入,逐步进行验算.
解答:当y=0时,

=

,x=72,整数对为(72,0);
当y=1时,

=

-1,x不是整数;
当y=2时,

=

-2

=4

=

,x=32,整数对为(32,2);
当y=3时,

=

-2

=6

-2

;
当y=4时,

=

-2

=6

-4;
当y=5时,

=

-2

=6

-2

;
当y=6时,

=

-2

=6

-2

;
当y=7时,

=

-2

=6

-2

;
当y=8时,

=

-2

=6

-4

=2

,x=8,整数对为(8,8);
当y=9时,

=

-2

=6

-6;
当y=10时,

=

-2

=6

-2

;
当y=11时,

=

-2

=6

-2

;
当y=12时,

=

-2

=6

-4

;
当y=13时,

=

-2

=6

-2

;
当y=14时,

=

-2

=6

-2

;
当y=15时,

=

-2

=6

-2

;
当y=16时,

=

-2

=6

-8;
当y=17时,

=

-2

=6

-2

;
当y=18时,

=

-2

=6

-6

=0,x=0,整数对为(0,18).
故整数对(X,Y)是(72,0),(32,2),(8,8),(0,18)共四个.
故选C.
点评:此题比较复杂,需对x、y的值进行逐一验算求解,找出符合条件的实数对.