单项选择题

如下程序运行时的输出结果是
#include<iostream>
using namespace std;
class ONE
int c;
public:
ONE( ):c(0)eout<<1;
ONE(int n):C(n)cout<<2;

class TW0
ONE onel;
ONE one2;
public:
TWO(int m):one2(m)eout<<3;

int main( )
TWO t(4);
return 0;

A) 3
B) 23
C) 123
D) 213