Volunteer studies are used to determine the infectious dose of Salmonella required to cause gastroenteritis. The curve obtained during the studies is shown in the diagram as line 2. Which of the following organisms could be represented by line 1 on this diagram? 
Definitions:
Seminar-Style Course
An educational class structured around group discussions, presentations, and interactive participation rather than lectures.
Thematic Apperception Test
A projective psychological test that involves creating stories about ambiguous scenes to uncover underlying thoughts and feelings.
Lack of Persistence
A trait characterized by giving up easily or not continuing in an activity or endeavor despite potential obstacles or challenges.
Low Need for Achievement
A psychological characteristic where an individual has little motivation or desire to achieve success or excel in tasks.
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