Insert a picture as a watermark. You can automatically turn a picture or a photo into a watermark that you can use to brand or decorate a document. On the Page Layout tab, in the Page Background group, click Watermark. Click Custom Watermark. Click Picture watermark, and then click Select Picture.
And that first defense, the first one that you want to be able to rely on, is truth. Yes, truth is a valid defense against a claim of Internet defamation. If what you say is true, then you cannot be successfully sued for defamation of character.
Bob's defense that he did not make the statement is not a truth defense; it is rebutting the assertion that the statement was made at all. The defense of truth in defamation claims means that the asserted statement assuming it was made was true. In your example, that issue never really arises because the complained about statement is one of opinion, not of fact.