Which of the following statements regarding website content are correct?

a. If you have two versions of a document on your website, Google recommends that you only allow the           indexing of the better version
b. Linking to a page inconsistently does not affect the way Google views the page/s.
c. Syndicating your content could lead to Google viewing the material as duplicate
d. Placeholders for pages which do not have content are never viewed as duplicate content by Google