Answer: a. a change in capitalization
Step-by-step explanation:
Brackets are commonly used for the purposes listed in answer choices C and D as a symbol to “tell” the reader that they’ve edited a quote to clarify things (for example, if the original quote is “She wandered down the rabbit hole” to clarify things, the writer might instead write “[Alice] wandered down the rabbit hole”. However, it’s not necessary to use brackets to signal a change in capitalization, in fact, most people don’t.
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