Argument structure questions will reference a portion of the passage in the question stem and then it is up to us to determine how this portion of the passage actually functions in the argument. Is it the conclusion? Is it a premise? Is it a counter-premise? Is it an example? Etc.
Usually (more like nearly always) the portion of the passage referenced comes directly from the passage. This is a very rare example where the portion of the passage referenced was not actually in the passage itself. It was an assumption in the passage, meaning it was unsaid but assumed by the author.
I hope this helps. Please let me know if you'd like me to expand further!