How do I make a Image/Button Link ?

Hi everynone...im trying to make a Facebook Button.

*Or any button, i just wanna open an URL in the Browser

I have the PNG image in my computer, what is the best option to import it...Sprite or TileBackground Object or other?

and how to make an event when the Object is touched/clicked it will make to open an URL in the Browser?

i tried with this [i've imported the image as Sprite]

*That event works only in PC, but when i see it in my Smartphone it wont open the URL, what could be the problem? i've tried with Default Android Browser, Chrome or UC Browser....still wont work the image LINK

Regards and thx for helping me in my initial adventure with C2