What will the output of the following questions:C++#include <bits/stdc++.h>using namespace std; int main(){     string a = "Hello";    string b = "World";    string c = b.append(a);    cout << c << endl;     return 0;}Hello worldWorld helloWorldHelloError

The output of the given C++ code will be "WorldHello".

Here's the step by step explanation:

1. The string a is initialized with the value "Hello".
2. The string b is initialized with the value "World".
3. The append() function is used to append the string a to the end of string b. So, b becomes "WorldHello".
4. The result of the append() function is assigned to the string c. So, c also becomes "WorldHello".
5. The value of c is printed out, which is "WorldHello".