What will be the output of the following C++ code?

#include <iostream>
using namespace std;
class sample
{
    private:
    int* i;
    int j;
    public:
    sample (int j);
    ~sample ();
    int& operator [] (int n);
};
int& sample::operator [] (int n)
{
    return i[n];
}
sample::sample (int j)
{
    i = new int [j];
    j = j;
}
sample::~sample ()
{
    delete [] i;
}
int main ()
{
    sample m (5);
    m [0] = 25;
    m [1] = 20;
    m [2] = 15;
    m [3] = 10;
    m [4] = 5;
    for (int n = 0; n < 5; ++ n)
    cout << m [n];
    return 0;
}

A. 252015105

B. 510152025

C. 51015

D. 51015210

Answer: Option A