A HELP in Unity C# code:

Question

hi there, This below code works absolutely fine : the DRAG AND DROP function works good. Here when correct image is droped on to its correct place it stays , but how to lock the image once its dropped in its correct position?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class manager1 : MonoBehaviour 

{

   public GameObject gorilla, dog, rabbit, lion, goat, gorillaBlack, dogBlack, rabbitBlack, lionBlack, goatBlack;

    Vector3 gorillaInitialPos, dogInitialPos, rabbitInitialPos, lionInitialPos, goatInitialPos;

    void Start()



    {
       gorillaInitialPos=gorilla.transform.position;
       dogInitialPos=dog.transform.position;
       rabbitInitialPos=rabbit.transform.position;
       lionInitialPos=lion.transform.position;
       goatInitialPos=goat.transform.position;

    }



//1
    public void Draggorilla()
    {  
        gorilla.transform.position = Input.mousePosition;

    }


//2
    public void Dragdog()
    {  
        dog.transform.position = Input.mousePosition;
    }


//3
    public void Dragrabbit()
    {  
        rabbit.transform.position = Input.mousePosition;
    }


//4
    public void Draglion()
    {  
        lion.transform.position = Input.mousePosition;
    }


//5
    public void Draggoat()
    {  
        goat.transform.position = Input.mousePosition;
    }





//1

public void Dropgorilla()
    {

        float Distance = Vector3.Distance(gorilla.transform.position, gorillaBlack.transform.position);
        if (Distance < 50)

        {
            gorilla.transform.position = gorillaBlack.transform.position;

        }
        else
        {
            gorilla.transform.position = gorillaInitialPos;

        }

    }
//2

        public void Dropdog()
    {

        float Distance = Vector3.Distance(dog.transform.position, dogBlack.transform.position);
        if (Distance < 50)
        {
            dog.transform.position = dogBlack.transform.position;

        }
        else
        {
            dog.transform.position = dogInitialPos;

        }

    }
//3

public void Droprabbit()
    {

        float Distance = Vector3.Distance(rabbit.transform.position, rabbitBlack.transform.position);
        if (Distance < 50)
        {
            rabbit.transform.position = rabbitBlack.transform.position;

        }
        else
        {
            rabbit.transform.position = rabbitInitialPos;

        }

    }
//4

public void Droplion()
    {

        float Distance = Vector3.Distance(lion.transform.position, lionBlack.transform.position);
        if (Distance < 50)
        {
            lion.transform.position = lionBlack.transform.position;

        }
        else
        {
            lion.transform.position = lionInitialPos;

        }

    }
//5

public void Dropgoat()
    {

        float Distance = Vector3.Distance(goat.transform.position, goatBlack.transform.position);
        if (Distance < 50)
        {
            goat.transform.position =goatBlack.transform.position;

        }
        else
        {
            goat.transform.position = goatInitialPos;

        }
    }
}