若有以下程序：
#include ＜iostream＞
using namespace std;
class Base

private:
int x;
protected:
int y;
public:
int z;
void setx(int i)

x=i;
int getx ()

return x;

;
class Inherit : private Base

private:
int m;
public:
int p;
void setvalue(int a, int b, intc, int d)

setx (

A．;
y=b;
z=c;
m=d;

void display()

cout＜＜getx () ＜＜","＜＜y＜＜","＜＜z＜＜","＜＜m＜＜end1;

;
int main ( )

Inherit A;
A.setvalue(1,2,3,4);
A.display ();
return 0;
A) 1,2,3,4

B．产生语法错误

C．4,3,2,1

D．2,3,4,5

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