You learn from a staff member that a prominent donor has notified the agency that she will no longer ...

You learn from a staff member that a prominent donor has notified the agency that she will no longer be providing support to the agency.
 
  You decide to contact the
  donor to see what may have led to her decision and to try to repair the damaged
  relationship. You learn from the donor that the organization made the most costly
  mistake in regards to maintaining donor loyalty. What was the mistake?
  a. The agency misspelled the donor's name in a newsletter.
  b. The agency acknowledged the wrong amount of a gift.
  c. The agency did not acknowledge a contribution.
  d. The agency asked for money in the thank-you note sent to the donor.