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

#include <iostream>
#include <vector>
using namespace std;
int main ()
{
    vector<bool> mask;
    mask.push_back(true);
    mask.flip();
    cout << boolalpha;
    for (unsigned i = 0; i < mask.size(); i++)
    cout << mask.at(i);
    return 0;
}

What does the 'sizeof' operator return in C++?

A. Size of a data type in bits

B. Size of a data type in bytes

C. Size of a variable in bytes

D. Size of a variable in bits

Which of the following is not a fundamental data type in C++?

A. Char

B. Float

C. String

D. Double

What is the purpose of the 'static' keyword in C++?

A. To declare a variable with dynamic storage duration

B. To declare a constant

C. To declare a variable with external linkage

D. To declare a variable with static storage duration

What is the difference between '++i' and 'i++' in C++?

A. None of the above

B. They both have the same effect

C. '++i' increments the value of 'i' before returning it, while 'i++' increments the value of 'i' after returning it

D. '++i' increments the value of 'i' after returning it, while 'i++' increments the value of 'i' before returning it