Holding companies: A. are firms that control the stock of other companies. B. were outlawed in New Jersey in 1888. C. allowed J. Pierpont Morgan to build a monopoly in the shipping business. D. were firms where union membership was required.

Option A is correct.

Explanation:

A holding company doesn't have any operations or active business itself but to own assets which are in form of shares of stocks in numerous corporations, limited liability companies, private equity funds, public stocks, patents etc