Quiz Challenge Code Not Working

function print(message) {
  document.write(message);
}

var correctAnswers = [];
var wrongAnswers = [];

var questions = [
  ["What is the capital of Mexico?", "mexico city"],
  ["How many legs does a insect has?", "6"],
  ["Name the author of Laravel?", "taylor otwell"],
  ["Who invented PHP?", "Hammad"],
  ["Which programming language is named after a snake?", "Phyton"],
  ["Which programming language is the name of a gem?", "Ruby"],
  ["Who is the first president of USA?", "Washington"]
]
print(questions[1][0]);
for ( var i = 0; i <= questions.length; ++i ) {
  var answer = prompt(questions[i][0]);
  answer.toLowerCase();
  if ( answer === questions[i][1] ) {
    correctAnswers.push(questions[i][0]);
  } else if ( answer !== questions[i][1] ) {
    wrongAnswers.push(questions[i][0]);
  }
}

print("You answered " + correctAnswers.length + " correctly");

for ( var i = 0; i <= correctAnswers.length; i++ ) {
  print(i + ". " + correctAnswers[i]);
}

for ( var i = 0; i <= wrongAnswers.length; i++ ) {
  print(i + ". " + wrongAnswers[i]);
}