Choose the correct option to fill? X so that the code given below implements the Heap sort.

#include <stdio.h> 
void heapify(int arr[], int n, int i) 
{ 
    int largest = i; // Initialize largest as root 
    int l = 2*i + 1; // left = 2*i + 1 
    int r = 2*i + 2; // right = 2*i + 2 
    if (l < n && arr[l] > arr[largest]) 
        largest = l; 
    if (r < n && arr[r] > arr[largest]) 
        largest = r; 
    if (largest != i) 
    { 
        swap(arr[i], arr[largest]); 
        heapify(arr, n, largest); 
    } 
} 
void heapSort(int arr[], int n) 
{ 
    for (int i = n / 2 - 1; i >= 0; i--) 
        heapify(arr, n, i); 
    for (int i=n-1; i>=0; i--) 
    { 
        X;
        heapify(arr, i, 0); 
    } 
} 
void printArray(int arr[], int n) 
{ 
    for (int i=0; i<n; ++i) 
        printf(“%d”,arr[i]);
    printf(“\n”);	    
} 
int main() 
{ 
    int arr[] = {12, 11, 13, 5, 6, 7}; 
    int n = sizeof(arr)/sizeof(arr[0]); 
    heapSort(arr, n); 
    printf(“Sorted array is \n"); 
    printArray(arr, n); 
}

A. swap(arr[0], arr[n])

B. swap(arr[i], arr[n])

C. swap(arr[0], arr[i])

D. swap(arr[i], arr[2*i])

Answer: Option C