How to show questions with corresponding image.,Unity Live Tutorial Quiz Game, how to make the text question into an image question

Im following the Live Tutorial in Quiz Game by Unity, how can i show the text question with an image. Here's the code

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 using UnityEngine.SceneManagement;
 using System.Collections.Generic;
 
 public class GameController : MonoBehaviour
 {
     public Text questionDisplayText; 
     public Text scoreDisplayText;
     public Text timeRemainingDisplayText;
     public SimpleObjectPool answerButtonObjectPool;
     public Transform answerButtonParent;
 
 
     public GameObject questionDisplay;
     public GameObject roundEndDisplay;
     public Text highScoreDisplay;
 
     private DataController dataController;
     private RoundData currentRoundData;
     private QuestionData[] questionPool;
 
     private bool isRoundActive = false;
     private float timeRemaining;
     private int questionIndex;
     private int playerScore;
     private List<GameObject> answerButtonGameObjects = new List<GameObject>();
 
     // Use this for initialization
     void Start ()
     {
         dataController = FindObjectOfType<DataController>();
 
         currentRoundData = dataController.GetCurrentRoundData();
         questionPool = currentRoundData.questions;
 
         timeRemaining = currentRoundData.timeLimitInSeconds;
         UpdateTimeRemainingDisplay();
         playerScore = 0;
         questionIndex = 0;
 
         ShowQuestion();
         isRoundActive = true;
     } 
 
     private void ShowQuestion()
     {
         RemoveAnswerButtons();
 
         QuestionData questionData = questionPool[questionIndex];
         questionDisplayText.text = questionData.questionText;
         
 
         for (int i = 0; i < questionData.answers.Length; i++)
         {
             GameObject answerButtonGameObject = answerButtonObjectPool.GetObject();
             answerButtonGameObject.transform.SetParent(answerButtonParent);
             answerButtonGameObjects.Add(answerButtonGameObject);
 
             AnswerButton answerButton = answerButtonGameObject.GetComponent<AnswerButton>();
             answerButton.Setup(questionData.answers[i]);
 
         }
     }
     
     private void RemoveAnswerButtons()
     {
         while (answerButtonGameObjects.Count > 0)
         {
             answerButtonObjectPool.ReturnObject(answerButtonGameObjects[0]);
             answerButtonGameObjects.RemoveAt(0);
         }
     }
 
     public void AnswerButtonClicked(bool isCorrect)
     {
         if (isCorrect)
         {
             playerScore += currentRoundData.pointsAddedForCorrectAnswert;
             scoreDisplayText.text = "Score: " + playerScore.ToString(); 
         } 
         if (questionPool.Length > questionIndex + 1)
         {
             questionIndex++;
             ShowQuestion();
         } else
         {
             EndRound();
         }
     }
     
     public void EndRound()
     {
         isRoundActive = false;
 
         dataController.SubmitNewPlayerScore(playerScore);
         highScoreDisplay.text = dataController.GetHighestPlayerScore().ToString();
 
 
         questionDisplay.SetActive(false);
         roundEndDisplay.SetActive(true); 
     }
 
     public void ReturnToMenu()
     {
         SceneManager.LoadScene("MenuScreen");
     }
 
     private void UpdateTimeRemainingDisplay()
     {
         timeRemainingDisplayText.text = "Time: " + Mathf.Round(timeRemaining).ToString();
     }
 
     // Update is called once per frame
     void Update ()
     {
         if (isRoundActive)
         {
             timeRemaining -= Time.deltaTime;
             UpdateTimeRemainingDisplay();
 
             if (timeRemaining <= 0f)
             {
                 EndRound();
             }
         }
     }
 }