counter always reports "all were right" when not so....

//use 2-d array to hold question-answer
var questions = [
                ["What is the capital of Georgia, USA?", "Atlanta"],
                ["How do you spell fart backwards?", "tarf"],
                ["What is the programming language that is abbreviated with js?", "JavaScript"],
                ["Who is the current president of the United States?","Barack Obama"],
                ["Who is the actor who played Batman in the original Batman TV series","Adam West"],
              ];
var correctAnswers = 0;
var question;
var response;
var answer;
var html;

//add functions here
function print(message) {
  document.write(message);
} 

//create a loop, ask 5 questions and compare to answer
//console.log(q_and_a[0][0]);
for ( var i=0; i < questions.length ; i++ ) {
      question = questions[i][0];
      answer = (questions[i][1]).toLowerCase;
     //use the prompt method to ask question i
     response = (prompt(question)).toLowerCase;
     //compare to the right answer with an if statement
     if (response === answer) {  
     //add to correctAnswers
       correctAnswers += 1;

     } 
}

html = "You got " + correctAnswers + " question(s) right!";
print(html);