Which of the following is the best example of ironic processing interfering with attempted thought ...

Which of the following is the best example of ironic processing interfering with attempted thought suppression?
 
  a. You are trying not to think about the fact that you made a fool of yourself at a party last weekend, but the thought pops into your head every few hours.
  b. You are trying not to think about the fact that you made a fool of yourself at a party last weekend, but the more you try not to think about it, the more the thought keeps popping into your head.
  c. The more you think about the fact that you made a fool of yourself at a party last weekend, the more mortifying and embarrassing the event seems.
  d. The more you think about the fact that you made a fool of yourself at a party last weekend, the less embarrassing it seems.