The “other half” that Jacob Riis referred to in his 1890 book, How the Other Half Lives, were the captains of industry. upper class. working poor. growing middle class.

C. The working poor

Explanation:

Jacob Riis was a muckraker that exposed the conditions that many immigrants lived in. Most immigrants, since they were different, were not given the same opportunities as others, and were therefore poor/moved to cities for jobs.

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