Question: HD-4 or Hydrodome number 4, was an early research hydrofoil watercraft, developed by which scientist, who was a Scottish-born scientist, inventor, engineer, and innovator who is credited with patenting the first practical telephone, and founding the American Telephone and Telegraph Company (AT&T), in 1885?
Context: Alexander Graham Bell (March 3, 1847 – August 2, 1922) was a Scottish-born scientist, inventor, engineer, and innovator who is credited with patenting the first practical telephone and founding the American Telephone and Telegraph Company (AT&T) in 1885. HD-4 or Hydrodome number 4 was an early research hydrofoil watercraft developed by the scientist Alexander Graham Bell.  It was designed and built at the Bell Boatyard on Bell's Beinn Bhreagh estate near Baddeck, Nova Scotia.  In 1919 it set a world marine speed record of 70.86 mph . Verizon Pennsylvania LLC, formerly traded as Bell of Pennsylvania, is the Bell Operating Company serving most of Pennsylvania.  The company was founded in 1879 as Bell Telephone Company of Philadelphia, owned by National Bell Telephone Company, which later became American Bell.  In 1899, the company became a subsidiary of American Telephone and Telegraph Company following its buyout of American Bell. The history of AT&T dates back to the invention of the telephone itself.  The Bell Telephone Company was established in 1879 by Alexander Graham Bell, the inventor of the telephone.  Bell also established American Telephone and Telegraph Company in 1885, which acquired the Bell Telephone Company and became the primary phone company in the United States.  This company maintained a monopoly on telephone service in the United States until anti-trust regulators split the company in 1982. Otto Julius Zobel (October 20, 1887 – January 1970) was an electrical engineer who worked for the American Telephone & Telegraph Company (AT&T) in the early part of the 20th century.  Zobel's work on filter design was revolutionary and led, in conjunction with the work of John R. Carson, to significant commercial advances for AT&T in the field of frequency division multiplex (FDM) telephone transmissions. In 1860, the Pacific Telegraph Act of 1860 called for the facilitation of communication between the east and west coasts of the United States of America.  Hiram Sibley of the Western Union Telegraph Company won the contract.  In 1861, Benjamin Franklin Ficklin joined Hiram Sibley in helping to form the Pacific Telegraph Company of Nebraska.  At the same time, Jeptha Wade was asked by Hiram Sibley to encourage the consolidation of telegraph companies in California, a process that had been underway there anyway, most notably involving the merger of the two largest intrastate companies following a lawsuit between them, the Alta Telegraph Company and the California State Telegraph Company.  The Overland Telegraph Company of California was thus formed with Horace W. Carpentier of the California State Telegraph Company serving as its president, and it began building east from Carson City, Nevada while its eastern counterpart, the Pacific Telegraph Company began building west from Omaha, Nebraska.   Upon their connection in Salt Lake City, Utah on October 24, 1861, the final link between the east and west coast of the United States of America was made.  The First Transcontinental Telegraph led to the immediate demise of the Pony Express.  The Pacific Telegraph Company of Nebraska and the Overland Telegraph Company of California were eventually absorbed into the Western Union Telegraph Company. The Telegraph Act 1870 (33 & 34 Vict.  c. 88.)  was an Act of the Parliament of the United Kingdom of Great Britain and Ireland.  It extended the Telegraph Act 1868 to cover the Channel Islands and the Isle of Man, thus allowing the British state to nationalise telegraph companies in these territories.  It gave orders to the Postmaster General to nationalize the Jersey and Guernsey Telegraph Company and the Isle of Man Electric Telegraph Company (the sale of which to the government had already been agreed in October 1868).  The Act further makes clear that the Submarine Telegraph Company, which had laid a commercial submarine telegraph cable across the English Channel in 1853, was not to be affected.  The Act was introduced partly due to the efforts of William Henry Preece, who was chief engineer of the Jersey and Guernsey Telegraph Company and a major shareholder, and had campaigned on behalf of the Channel Islands' inclusion in the Act of 1868. Mabel Gardiner Hubbard (November 25, 1857 – January 3, 1923), was the daughter of Boston lawyer Gardiner Greene Hubbard, who was the first president of the Bell Telephone Company.  As the wife of Alexander Graham Bell, an eminent scientist and the inventor of the first practical telephone, she took the married name Mabel Bell. The Pacific Telegraph Act of 1860 called for the facilitation of communication between the east and west coasts of the United States of America.  Hiram Sibley of the Western Union Telegraph Company won the contract.  In 1861, Benjamin Franklin Ficklin joined Hiram Sibley in helping to form the Pacific Telegraph Company of Nebraska.  At the same time, Jeptha Wade was asked by Hiram Sibley to consolidate smaller telegraph companies in California.  While the Pacific Telegraph Company built west from Omaha, Nebraska, the Overland Telegraph Company of California was thus formed and built east from Carson City, Nevada.  With their connection in Salt Lake City, Utah on October 24, 1861, the final link between the east and west coasts of the United States of America was made by telegraph.  The First Transcontinental Telegraph lead to the immediate demise of the Pony Express.  The Pacific Telegraph Company and the Overland Telegraph Company of California were eventually absorbed into the Western Union Telegraph Company. Theodore Gary & Company was a 20th-century independent telephone firm in the United States.  Among its subsidiaries was the Associated Telephone and Telegraph Company, which controlled telephone companies in Latin America and telephone manufacturing interests in Europe in the 1920s and 1930s.  In that capacity, Associated, formed in 1925, was the only other serious U.S. rival of International Telephone and Telegraph in Europe before World War II.  Associated also exercised influence over the telephone networks in the Dominican Republic and Columbia.  In 1930 it formed a new subsidiary, the General Telephone and Electric Corporation, with Transamerica Corporation and British investors, to strengthen overseas manufacturing and operations in competition with ITT.  This was headed by Theodore Gary's son, Hunter Larrabee Gary.  It would ultimately merge into the General Telephone Corp. (later known as GTE) in 1955.
Answer: Alexander Graham Bell