She has experienced horizontal social mobility.
It means that she has only moved horizontally - her paycheck has stayed the same, she didn't get any special promotions or anything. The only thing that changed is the place where she works - if she were given more salary, it would be a vertical social mobility.
Answer: " the bystander effect " .
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Hope this helps!
Best wishes in your academic endeavors —
and within the "Brainly" community!
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