How to detect which block is pressed using javascript

Hi I am trying to detect which cube is pressed but the code. I just have 3 simple cubes which act as a button I want to detect which is pressed at what. i am using it does not work properly when ever i click it clicks all cubes using Javascript

 #pragma strict
 
 function Start () {
 
 }
 
 function Update () {
 
 if(Input.GetMouseButtonDown(0))
 {
 var hit: RaycastHit2D = Physics2D.Raycast(transform.position, -Vector2.up);
 
 
 
 if(hit.transform.gameObject.tag.Equals("Box 3")){
 Debug.Log("hit 1");
 }
 if(hit.transform.gameObject.tag.Equals("Box 2")){
 Debug.Log("hit 2");
 }
 if(hit.transform.gameObject.tag.Equals("Box 1")){
 Debug.Log("hit 3");
 }
 }
 
 }