Question: Three Nationwide Plaza is a 408 ft(124m) postmodern highrise building located at the address 3 Nationwide Plaza in Downtown Columbus, Nationwide Plaza is the headquarters of Nationwide Mutual Insurance Company, and affiliated companies, are a group of large U.S. insurance and financial services companies based in Columbus in which US state (acronym)?

Context paragraphs:
Atlantic Mutual Insurance Company: The Atlantic Mutual Insurance Company is a mutual insurance company which offers personal, marine, commercial property, and casualty insurance.  It is part of the Atlantic Mutual Companies, which includes Centennial Insurance Company.  Its corporate headquarters are at 140 Broadway, a block from the World Trade Center.

Surplus note: In the United States a contingent surplus note is a bond-like instrument issued by an insurance company.  These securities are subordinated obligations, and fall at the very bottom of the operating insurance company's capital structure.  They are issued primarily by mutual insurance companies, which are not public and owned instead by their policy holders.  Surplus notes are debt-like in that they pay a coupon and have a finite maturity.  However, in many cases, state insurance regulators have allowed insurance companies to classify the capital raised via surplus notes as “surplus” (which is the statutory equivalent of equity), because surplus note holders are last in line to make a claim on the company's assets in a default scenario, much like where equity holders reside in a public company.  The motivation for mutual companies to issue these instruments was to raise surplus (or equity) in response to new risk-based capital guidelines developed in the early 1990s.  Because mutual companies are owned by policyholders, not shareholders, there was no alternative method to raise surplus or equity.  While surplus note holders have last claim on the assets of the operating insurance company, it is important to realize that this claim is at the operating company level, which is still ahead of holding company obligations.

FMG Insurance: FMG Insurance (formerly Farmers' Mutual Group) is a mutual insurance company in New Zealand that was established from a merger of the Farmers' Mutual Insurance Association, Taranaki Farmers' Mutual Insurance Association and Primary Industries Insurance Company Limited in 1978.  The company is incorporated under the Farmers’ Mutual Group Act 2007 and can trace its origins back to the original farmer's fire mutual organisations established in 1905.

The Norfolk &amp; Dedham Group: The N&D Group is a group of mutual insurance companies based in Dedham, Massachusetts.  The group comprises three regional property and casualty insurance companies which market personal and commercial insurance product lines through independent insurance agents.  The group conducts business in New England, New Jersey, Arkansas, and Missouri, and wrote about a third of a billion dollars in annual insurance premium in 2013.  Founded as The Norfolk Mutual Fire Insurance Company in 1825, the group is one of the oldest mutual insurance companies in the United States.

Physicians Mutual: Physicians Mutual is a privately held insurance company headquartered in Omaha, Nebraska, United States, that consists of Physicians Mutual Insurance Company and Physicians Life Insurance Company.  Founded as Physicians Mutual Insurance Company in 1902 by Edwin E. Elliott, Physicians Mutual began by selling health insurance to medical professionals.  Policies were offered to the general public starting in 1962, and by 1970 the company expanded into life insurance when it founded Physicians Life Insurance Company.  Today the company offers a variety of insurance products, annuities, Medicare, Medigap, Medicare Supplement, Term Life Insurance, Whole Life Insurance, Cancer and funeral pre-planning services.  It holds over US$3 billion in assets and employs over one thousand people.  Robert A. Reed is chief executive officer and president.

Three Nationwide Plaza: Three Nationwide Plaza is a 408 ft(124m) postmodern highrise building located at the address 3 Nationwide Plaza in Downtown Columbus, Ohio.  The building is part of the larger multi-building complex known as Nationwide Plaza.  Nationwide Plaza is the headquarters of Nationwide Mutual Insurance Company.  Three Nationwide Plaza is the 10th tallest building in Columbus.  Construction on the building finished in December 1988.  The architect responsible was the NBBJ Group and the building design follows a postmodern style.  The building was constructed for approximately $89 million and the main materials used were glass, steel, and concrete.

Western Mutual Insurance Group: Western Mutual Insurance Group is an American group of Property and Casualty Insurance companies, made up of Western Mutual Insurance Company, its sister company Residence Mutual Insurance Company, and their jointly owned subsidiary, Arizona Home Insurance Company.  Based in Irvine, CA, the group writes direct property and casualty insurance in Arizona, California, Colorado, New Mexico, Nevada, Utah and Texas for preferred homeowners.  The Western Mutual Insurance Group has a financial strength rating of 'A+' (Superior) by A.M. Best, a Nationally Recognized Statistical Rating Organization (NRSRO) by the United States Securities and Exchange Commission.

Nationwide Mutual Insurance Company: Nationwide Mutual Insurance Company and affiliated companies is a group of large U.S. insurance and financial services companies based in Columbus, OH.  The company also operates regional headquarters in Des Moines, IA; San Antonio, TX; Gainesville, FL; Raleigh, NC; and Westerville, OH.  Nationwide currently has approximately 31,000 employees, and is ranked #69 in the most recent Fortune 500.  Nationwide is currently ranked #71 in Fortune's "100 Best Companies to Work For".

One Nationwide Plaza: One Nationwide Plaza is a 40-story skyscraper in Columbus, Ohio that serves as the corporate office headquarters of Nationwide Mutual Insurance Company.  It is part of the complex of buildings known as Nationwide Plaza.

Ohio Mutual Insurance Group: "Ohio Mutual Insurance Group" is a group of property and casualty insurance companies based in Bucyrus, Ohio.  The group is composed of three affiliates: Ohio Mutual Insurance Company, United Ohio Insurance Company and Casco Indemnity Company.  As a mutual insurance company, Ohio Mutual Insurance Group is not a stock company but one that is mutually owned by its policyholders.  A board of directors and an appointed president and chief executive officer manage the company.

Supporting paragraphs: Three Nationwide Plaza Nationwide Mutual Insurance Company
Answer: OH