Quoted from jrpinball:This has been covered a number of times already.
The second option in the poll is pointless unless all the other external metal parts are also grounded to the transformer base.
Lots of things have been covered before. And new people keep coming in. So items will get talked about again. And then again. I mean, can you really ask someone to go search 100s of pages and thousands of posts?
If you know a link that sheds light, do not berate someone for asking the same old question that has been asked before. Say, "Here you are" and provide a link.