old.js

const quiz = [
  ["What is Superman's real name?", "Clark Kent"],
  ["What is Wonder Woman's real name?", "Diana Prince"],
  ["What is Batman's real name?", "Bruce Wayne"]
];

function start(quiz) {
  let score = 0;
  
  // main game loop
  for (const [question, answer] of quiz) {
    const response = ask(question);
    check(response, answer);
  }
  // end of main game loop
  
  gameOver();
  
  // ---------- function declarations ---------- 

  function ask(question) {
    return prompt(question);
  }
  
  function check(response, answer) {
    if (response === answer) {
      alert('Correct!');
      score++;
    } else {
      alert(`Wrong! The correct answer was ${answer}.`);
    }
  }
  
  function gameOver() {
    alert(`Game Over, you scored ${score} point${score !== 1 ? 's' : ''}`);
  }
  
  // ---------- functio ---------- 
}

start(quiz);