iOS测验应用程序，混乱多项选择但记住正确的答案

Question

我正在关注Ray Wenderlich的一个教程，该教程涉及创建一个可以在Apple TV上显示问题的测验，以及要回答的设备。在这方面，很少有时间花在回答问题的逻辑上。问题存储在plist文件中，其中第一个可能的答案始终是正确的答案。在代码中，它显示为：

- (void)startQuestion
{
  // 1
  int questionIndex = arc4random_uniform((int)[self.questions count]);
  NSMutableArray *questionArray = [self.questions[questionIndex] mutableCopy];
  [self.questions removeObjectAtIndex:questionIndex];

  // 2
  NSString *question = questionArray[0];
  [questionArray removeObjectAtIndex:0];

  // 3
  NSMutableArray *answers = [[NSMutableArray alloc] initWithCapacity:[questionArray count]];
  self.currentQuestionAnswer = -1;
  self.currentQuestionAnswersReceived = 0;

  while ([questionArray count] > 0)
  {
    // 4
    int answerIndex = arc4random_uniform((int)[questionArray count]);
    if (answerIndex == 0 && self.currentQuestionAnswer == -1)
    {
      self.currentQuestionAnswer = [answers count];
    }
    [answers addObject:questionArray[answerIndex]];
    [questionArray removeObjectAtIndex:answerIndex];
  }

  // 5
  [self sendToAllPeers:[kCommandQuestion stringByAppendingString:
            [NSString stringWithFormat:@"%lu", (unsigned long)[answers count]]]];
  [self.scene startQuestionWithAnswerCount:[answers count]];
  [self.mirroredScene startQuestion:question withAnswers:answers];
}

当在本教程结束时运行应用程序时，它总是使'A'成为正确的答案。有没有办法告诉应用程序plist中每个问题下的第一项是正确的，但让它在ABCD之间随机化，以便每次运行应用程序时答案都是不同的选择？