Which of the following types of content would not be appropriate to email to someone in the decision stage of the Buyer’s Journey?

Which of the following types of content would not be appropriate to email to someone in the decision stage of the Buyer’s Journey?
  A)  A report on the ROI of regular business blogging.
  B)  A product demo of a blogging tool.
  C)  An infographic about the benefits of business blogging.
  D)  A case study on a business who saw an increase in traffic after blogging regularly.