Adding one onClick listener to Button Array cause NullReferenceException

Question

Hello guys i'm trying to write a game scenario which includes multiple levels.In the scenario the user will try to memorize the words on the screen then try to choose right ones by clicking buttons. I created multiple buttons as a GameObject (for specific reasons)

so here's how it goes

    public GameObject[] buttons = new GameObject[7];

These are my buttons.I created them in my canvas as buttons but in script i treat them like a GameObject.

 void wordsToButton()
{        
    for(int i = 0; i < wordsTxt.Length; i++)
    {          
        buttons[i].GetComponentInChildren<Text>().text = wordsTxt[i].GetComponent<Text>().text;
        buttons[i].transform.position = new Vector2(Random.Range(30, Screen.width - 20), Random.Range(30, Screen.height - 50));
    }
    for(int i=0; i <differentWords.Length; i++)
    {
        buttons[i+5].GetComponentInChildren<Text>().text = differentWords[i].GetComponent<Text>().text;
        buttons[i+5].transform.position = new Vector2(Random.Range(30, Screen.width - 20), Random.Range(30, Screen.height - 50));
    }
}

In here i am trying to edit button's text and give it a random position.Additionaly i also put some wrong words.It works fine.

 public void buttonListeners()
{
    for(int i=0; i < buttons.Length-1; i++)
    {
        buttons[i].GetComponent<Button>().onClick.AddListener(() =>
        {
            int n = i;
            if(buttons[n].GetComponent<Text>().text == differentWords[0].GetComponent<Text>().text || buttons[n].GetComponent<Text>().text == differentWords[1].GetComponent<Text>().text)
            {
                correctAnswers--;
            }
            else
            {
                correctAnswers++;
            }
        });
    }
}

In here i gave listeners to buttons.When user click on buttons it checks for correct answer.

 public void level2()
{
    if (levels[2].activeSelf == true)
    {
        differentWords[0].SetActive(false);
        differentWords[1].SetActive(false);
        levels[0].SetActive(false);
        levels[1].SetActive(false);
        levels[3].SetActive(false);
        timer1 = 10;
        InvokeRepeating("countDown1", 0.01f , 1);           
    }
    wordsToButton();
    buttonListeners();
}

This is the level which i talked about.So when i click a button on the screen it gives me this error:

NullReferenceException: Object reference not set to an instance of an object Word+c__AnonStorey0.<>m__0 () (at Assets/categories/Word.cs:184)

line 184 is :

 if(buttons[n].GetComponent<Text>().text == differentWords[0].GetComponent<Text>().text || buttons[n].GetComponent<Text>().text == differentWords[1].GetComponent<Text>().text)

What should i do ? I know that I'm trying to reach null values.But it is not null actually, thus far my code works perfectly fine and i can see button's texts, all of them correct but when i click a button,it gives me this error.

Edit: I understood why it gives me errors.Writing this for helping some people. Because i try to get a Button's Text component. Which is null. I fixed my code with

if(buttons[n].GetComponentInChildren<Text>().text == differentWords[0].GetComponent<Text>().text || buttons[n].GetComponentInChildren<Text>().text == differentWords[1].GetComponent<Text>().text)