单项选择题
A.template<CLASS Q> B.template<CLASS Q> Q F(Q {retum Q+x;) Q F(Q {return x+x;} C.template<classT> D.template<class T> TF(T {return x*x;) Bool F(t{return x>1;)
A.operator-( B.operator-(y, C.operator-( D.operator-(x,
A.void f1(double&{--x;) B.double f2(double {return x-1.5;) C.void f3(double {--x;) D.double f4(double *{--*x;retum *x;}