Question: Franklin Delano Roosevelt Wakefield, is an innovative American player, of which instrument, in the bluegrass music style, Wakefield is known for his collaborations with a number of important and well-known bands, including The Stanley Brothers?

Context paragraphs:
Murphy Grist Mill: Murphy Grist Mill, also known as the Old Mill, is a historic grist mill located at Poughquag, Dutchess County, New York.  It was built in 1889, and is a two-story, front-gabled, vernacular frame building with a stone and concrete foundation.  It has a one-story, hipped roof porch supported by simple contemporary posts.  Also on the property are the contributing ruins of a stone mill dam.  During his 1909 campaign for New York State Senate, Franklin Delano Roosevelt gave a political speech from the porch of the mill building.  The mill remained in use until about 1940.  Franklin Delano Roosevelt Jr. purchased the property in 1949 and the mill was used primarily for storage.  During the mid-1980s, it was given to the Town of Beekman and restoration began in 2014.

Franklin Delano Roosevelt Memorial: The Franklin Delano Roosevelt Memorial is a presidential memorial in Washington D.C. dedicated to the memory of Franklin Delano Roosevelt, the 32nd President of the United States, and to the era he represents.  For the memorial's designer, landscape architect Lawrence Halprin, the memorial site represents the capstone of a distinguished career, partly because the landscape architect had fond memories of Roosevelt, and partly because of the sheer difficulty of the task.

Franklin Delano Roosevelt Bridge: The Franklin Delano Roosevelt Bridge is an international bridge, which connects Maine State Route 189 in the community of Lubec, Maine in the United States with New Brunswick Route 774 on Campobello Island in the Canadian province of New Brunswick across the Lubec Narrows.  The decked steel truss bridge is named for Franklin Delano Roosevelt, the 32nd President of the United States, who maintained a summer retreat on Campobello (now preserved as Roosevelt Campobello International Park).  It is the island's only road connection to the mainland of North America; all of the island's transportation connections to the rest of New Brunswick are by ferry.

Frank Wakefield: Franklin Delano Roosevelt Wakefield (born June 26, 1934) is an innovative American mandolin player in the bluegrass music style.  Wakefield is known for his collaborations with a number of important and well-known bands, including Red Allen, Don Reno, Jerry Garcia, David Grisman, The Stanley Brothers, and the Greenbriar Boys.

Frederic Adrian Delano: Frederic Adrian Delano II (September 10, 1863 – March 28, 1953) was an American railroad president born in Manhattan, New York.  He was a member of the Delano family as a son of Warren Delano Jr. and Catherine Robbins Lyman, brother of Sara Ann Delano, and uncle of U.S. President Franklin Delano Roosevelt.  His philanthropic work through the Commercial Club of Chicago strongly impacted his nephew's Presidential policies.  Delano was Chairman of the Committee on the Regional Plan for New York and Its Environs, which released the regional plan for New York on May 27, 1929.  He was also a prime organizer of the "Regional Plan for New York and Its Environs," published in 1928.  He was also a member of the Commercial Club of Chicago which affected the development of Chicago in the 19th and 20th centuries.  Delano was the first vice-chairman of the Federal Reserve and the National Resources Planning Board.

Outer Drive Bridge: The Outer Drive Bridge, also known as the Link Bridge, is a double-deck bascule bridge across the Chicago River in Chicago, Illinois, United States.  Construction was started in 1929 and was completed in 1937 as one of the Public Works Administration's infrastructure projects in Chicago.  The bridge is officially named the Franklin Delano Roosevelt Memorial Bridge to honor the centennial anniversary of the birth of Franklin Delano Roosevelt.  It was planned by the Chicago Plan Commission, using Hugh E. Young as the consulting engineer, was designed by the Strauss Engineering Company, built by the American Bridge Company, and erected by Ketler and Elliot Company.  It crosses near the mouth of the Chicago River.

The Stanley Brothers: The Stanley Brothers were an American bluegrass duo made up of brothers Carter Stanley (1925–1966) and Ralph Stanley (1927–2016).  Ralph and Carter performed as The Stanley Brothers with their band, The Clinch Mountain Boys, from 1946 to 1966.  Ralph kept the band name when he continued as a solo after Carter's death, from 1967 until his own death in 2016.

Lonesome Pine Fiddlers: The Lonesome Pine Fiddlers (1938- 1966) were an early bluegrass band which included such notable "first generation" bluegrass musicians as Ezra Cline, Bobby Osborne, Paul Williams, Melvin Goins, Charlie Cline, Curly Ray Cline, Larry Richardson and for a short time Jimmy Martin.  The group was started by Ezra Cline and Curly Ray Cline and was originally named "Cousin Ezra and the Lonesome Pine Fiddlers".  The Clines came from a large family consisting of musically talented people.  Ray and Charlie's father, Charlie, was a talented banjo player and the women in the family, Geraldine and Bobbi, were great singers.  For reasons unknown, Bobbi and Geraldine never joined the band on the road but often joined in at home, especially when notable Country singers, such as Bill Monroe, Lester Flatt and Earl Scruggs, and Hank Williams, came visiting.  None of them ever had a music lesson yet excelled on every instrument they touched.  Natives of the Gilbert Creek region of southern West Virginia, Cousin Ezra, along with brothers Ireland (Lazy Ned) and Curly Ray Cline, were part of the original Lonesome Pine Fiddlers from about 1938, a group that worked on radio at WHIS Bluefield, West Virginia.  During World War II, Ned was killed in action.  When the Pine Fiddlers resumed regular daily broadcasts, Charlie, who played multiple instruments, joined them on a regular basis.  Charlie returned to the Fiddlers briefly before becoming a member of Bill Monroe's Blue Grass Boys.  During 1952-1955, Charlie worked off and on with Monroe, recording some 38 songs, all on Decca.  It has been said that he played every instrument at one time or another in the Monroe group except mandolin.  Charlie spent most of 1953 back with the Lonesome Pine Fiddlers working at WJR radio in Detroit.  When Ezra brought the band to Pikeville, Kentucky, in November, Charlie rejoined Bill Monroe.  In 1954, Charlie did a session, playing lead guitar, with the Stanley Brothers and also another one on RCA with the Fiddlers, although he was not otherwise working with them at the time.  He also worked briefly as a sideman with the Osborne Brothers, although he did not record with them.  By 1958, Charlie (electric lead guitar) and his wife, Lee (electric bass), had rejoined Ezra and Curly Ray in the Lonesome Pine Fiddlers, who were experimenting with a more modern sound and working a TV show in Huntington, West Virginia, in addition to daily radio in Pikeville.  In his later years, Charlie was with the Stanley Brothers.  Curly Ray also played with the Stanley Brothers at a different time as their fiddler.  Curly Ray was one of the best fiddlers in Bluegrass.  This most talented family of musicians were the best, surpassed by none.  Finally, on October 1, 2009, The Lonesome Pine Fiddlers got their due when they were inducted into the International Bluegrass Hall of Fame at the Ryman Theater (the original home of the Grand Ole Opry).  Bobby Osborne, Melvin Goins and Paul Williams were there to receive the bands award.  In the crowd of a sold out theater was the son of Ezra Cline, Scotty Ireland Cline, who recalled being in that same theater as a child sitting on stage and watching the Fiddlers play.  (At the time, the Opry had bleachers for family just off stage).  The final act of the evening at the IBMA Awards was the playing of "Pain in my Heart" by Osborne, Goins and Williams along with a Song from the Dillards, who were also inducted the same evening.

Peruvian Debate Association: The Peruvian Debate Association (PDA) is a legally ordained, non-profit institution, which organizes and coordinates activities to promote and increase debate in and among schools and universities in Peru.  This association was founded in September 2002, by Sixto Ramos, Philosophy, Economics and Peruvian History teacher at Colegio Franklin Delano Roosevelt and representatives from 6 other schools; Santa María Marianistas, San Ignacio de Recalde, Markham College, Casuarinas, Newton and Carmelitas.  In 2003 the Peruvian Debate Association along with other non-member schools and colleges helped Colegio Franklin Delano Roosevelt organize the World Schools Debating Championship 2003 in Lima, Peru; the grand final was held at a packed auditorium at Universidad de Lima with well over 1000 people attending.

Sara Delano Roosevelt Park: Sara Delano Roosevelt Park is a 7.8 acre park in the Lower East Side of the New York City borough of Manhattan.  The park, named after Sara Roosevelt (1854–1941), the mother of President Franklin Delano Roosevelt, stretches north-south along seven blocks between East Houston Street on the Lower East Side and Canal Street in Chinatown, bordered by Chrystie Street on the west and Forsyth Street on the east.  The park is operated and maintained by the New York City Department of Parks and Recreation.

Supporting paragraphs: Frank Wakefield The Stanley Brothers
Answer: mandolin