The correct option is A George H.W. Bush
The U.S.-Soviet Strategic Arms Reduction Treaty, known as START, was signed on July 31, 1991 by U.S. President George H.W. Bush and Soviet President Mikhail Gorbachev. START negotiated the largest and most complex arms control treaty in history, and its final implementation in late 2001 resulted in the removal of about 80 percent of all strategic nuclear weapons then in existence.