2  2.1.2   Sufficient proof of an anti -doping rule violation under Article 2.1 is established by any of the following: presence of a Prohibited  Substance  or its Metabolites  or Markers  in the Athlete’s  A Sample  where the Athlete  waives analysis of the B Sample  and the  B Sample  is not analyzed; or, where the Athlete’s  B Sample  is  responsibilities according to Code Article 21.3.