mark comments/replies/multiple answers as correct

A question has been answered correctly, but there is also a different way to do it. Mark multiple answers as correct/or mark a comment as correct.
Enhancement 

Example from SolidWorks:

How do I hide a body?

right click, hide body

 you can also hit 'tab' while the mouse is over it

when mating you can hit alt and the surface where your mouse is over it will temporarily be hidden



All of those answers are correct and it would be great to show all of them as a valid answer.



Edit: tags, formatting