<prompt> 100 bioavailability is seen with which routeOralIntravenousRectalSubcutaneous  <response>: Bioavailability is defined as the fraction of unchanged drug reaching the systemic circulation following administration by any route.In case a drug is given orally, the bioavailability shall be less than 100. This is due to The incomplete extent of absorption First pass metabolismRoutes of Administration, Bioavailability, and General Characteristics 