Conversely, No Fault or Negligence would not apply in  the following circumstances: (a) a positive test resulting from a mislabeled or contaminated vitamin or nutritional supplement ( Rider s are responsible for what they ingest (Article  2.1) and have been warned against the possibility of supplement contaminat ion); (b) the Administration of a Prohibited Substance by the Rider ’s personal physician or trainer without disclosure to the Rider  (Rider s are responsible for their choice of medical personnel and for advising medical personnel that they cannot be given a ny Prohibited Substance); and (c) sabotage of the Rider ’s food or drink by a spouse, coach or other Person within the Rider ’s circle of associates ( Rider s are responsible for what they ingest and for the conduct of those Persons to whom they entrust access  to their food and drink).