A region of a state had an outbreak of hepatitis. When reviewing the histories of the victims, it was noted that they had received either whole blood or blood products within the past 9 months. On further investigation, it was determined that all blood and blood products had come from one organization's blood lab that had failed to test their donors for hepatitis. This transmission of infection to others is known as: a. Direct Contact c. Common Vehicle b. Indirect Contact d. Vector