Final answer:
In paragraph 3, the term "backstory" most likely refers to the background information that helps readers understand the subject in a particular context.
Step-by-step explanation:
In paragraph 3, the term "backstory" most likely refers to the background information that helps readers understand the subject in a particular context. It is the details about someone's past or the events that happened before the main story or topic. In the given context, the term is used to explain how including background information can help place the subject in time and culture, enhancing readers' understanding.