please i need help in appending image src into select option in javascript 

here is my code : 

```
 $.ajax({
       type: "POST",
       url: "http://10.102.220.119:8001/api/1/device/devices",
       dataType: "json",
       data: { ids : ids}, 
       success:function(data){
        for (var i = 0 ; i<data.length;i++){
            var image = data[i].image;
            var mime = data[i].mime;

            var img = new Image();
            img.src = "data:"+mime+";base64,"+image;
            document.body.appendChild(img);

            /*var option = document.createElement("option");
            option.data-img-src = img.src;
            var select = document.getElementById("selectImage");
            select.appendChild(option);*/
        }

    }

 });

```

i use 

```
option.data-img-src = img.src; 

```

but it display this error : 

```
Invalid left-hand side in assignment 

```

please any help