Question: What year did Larry McMurtry's screenplay adaptation about the complex emotional and homosexual relationship between Ennis Del Mar and Jack Twist in the American West from 1963 to 1983 win him an oscar?

Context paragraphs:
Jack Twist: Jack Twist is a fictional character of the short story "Brokeback Mountain" by Annie Proulx and the 2005 Academy Award-winning film adaptation of the same name directed by Ang Lee, where he is portrayed by American actor Jake Gyllenhaal.  Jack's story is depicted by the complex, sexual, and romantic relationship he has with Ennis Del Mar in the American West from 1963 to 1983.

List of accolades received by Brokeback Mountain: "Brokeback Mountain" is a 2005 American epic romantic drama film directed by Ang Lee.  Based on the short story of the same name by author Annie Proulx, the story was adapted by Larry McMurtry and Diana Ossana.  The film depicts the complex emotional and sexual relationship between two men, Ennis Del Mar and Jack Twist (played by Heath Ledger and Jake Gyllenhaal, respectively) in the American West between 1963 and 1983.  Michelle Williams, Anne Hathaway, Linda Cardellini, Randy Quaid, Anna Faris, and Kate Mara feature in supporting roles.

Del Mar racetrack: Del Mar Thoroughbred Club racetrack is an American Thoroughbred horse racing track at the Del Mar Fairgrounds in the seaside city of Del Mar, California, 20 mi north of San Diego.  With a capacity of 44,000, it is the second largest horse-racing venue in the western United States, after the nearby Santa Anita Park.  The facility is owned by the State of California and leased by the Del Mar Thoroughbred Club, it is known for the slogans: "Where The Turf Meets The Surf" as well as "Cool as Ever."  It was built by a partnership including Bing Crosby, actors Pat O'Brien, Gary Cooper, Joe E. Brown, Charles S. Howard and Oliver Hardy.

Oak Tree Racing Association: In 1968, the Del Mar Thoroughbred Club, operators of Del Mar Racetrack in Del Mar, California, decided to inform California racing authorities that they did not intend to use the fall dates they were granted and to instead race only a summer meet.  Clement L. Hirsch, Louis R. Rowan, both leading horse owners, and veterinarian Dr. Jack Robbins, as well as other horsemen and fans were deeply opposed to the move which had the effect of ending live racing in Southern California from September 1 to November 1.

Ennis Del Mar: Ennis del Mar (Del Mar in the film) is the fictional main character of the short story "Brokeback Mountain" by Annie Proulx and the 2005 Academy Award-winning film adaptation of the same name directed by Ang Lee.  Ennis's story is depicted by his complex sexual and romantic relationship with Jack Twist in the American West, over two decades from 1963 to 1983.  In the film, he is portrayed by Heath Ledger, who was nominated for the Academy Award for Best Actor for his performance.

Brokeback Mountain: Brokeback Mountain is a 2005 American neo-western romantic drama film directed by Ang Lee and produced by Diana Ossana and James Schamus.  Adapted from the 1997 short story of the same name by Annie Proulx, the screenplay was written by Ossana and Larry McMurtry.  The film stars Heath Ledger, Jake Gyllenhaal, Anne Hathaway, and Michelle Williams, and depicts the complex emotional and homosexual relationship between Ennis Del Mar and Jack Twist in the American West from 1963 to 1983.

Larry McMurtry: Larry Jeff McMurtry (born June 3, 1936) is an American novelist, essayist, bookseller, and screenwriter whose work is predominantly set in either the old West or in contemporary Texas.  His novels include "Horseman, Pass By" (1962), "The Last Picture Show" (1966) and "Terms of Endearment" (1975), which were adapted into films earning 26 Academy Award nominations (10 wins).  His 1985 Pulitzer Prize-winning novel "Lonesome Dove" was adapted into a television miniseries that earned 18 Emmy Award nominations (seven wins), with the other three novels in his "Lonesome Dove" series adapted into three more miniseries, earning eight more Emmy nominations.  McMurtry and cowriter Diana Ossana adapted the screenplay for "Brokeback Mountain" (2005), which earned eight Academy Award nominations with three wins, including McMurtry and Ossana for Best Adapted Screenplay.

Binglin Stable: Binglin Stable in Moorpark, Ventura County, California was a stock farm established during the latter part of the 1930s to race and breed Thoroughbred horses.  The stable was owned by entertainer Bing Crosby and close friend, Lindsay Howard.  Crosby was a fan of Thoroughbred horse racing who in 1937 became a founding partner and member of the Board of Directors of the Del Mar Thoroughbred Club, operators of Del Mar Racetrack in Del Mar, California.  Lindsay Howard's father, Charles S. Howard, was a millionaire businessman who was also a founding partner and director of the Del Mar Thoroughbred Club and who owned a successful racing stable that included the 1938 U.S. Horse of the Year, Seabiscuit.  Upon his retirement from riding, future Hall of Fame jockey Albert Johnson, a childhood friend of Crosby, became the stable's trainer.

Illa del Mar: Illa del Mar ("Sea Island") is a complex of four buildings, including two skyscrapers, located in Barcelona, Catalonia, Spain.  The tallest skyscrapers is "Illa del Mar 1" with 99 meters (325 feet) tall and has 29 floors and "Illa del Mar 2" with 77 meters tall and has 23 floors.  The Illa del Mar complex is located in the district of Sant Martí on Passeig del Taulat street.

San Diego Sockers (2009–): San Diego Sockers are an American professional indoor soccer franchise playing in the Western Division of the Major Arena Soccer League, representing the San Diego area since 2009.  Their first arena was the Chevrolet Del Mar Arena at the Del Mar Fairgrounds adjacent to the Del Mar Racetrack in Del Mar, California.  They switched to the Valley View Casino Center, the original home of the MISL Sockers, for the 2012–2013 season.

Supporting paragraphs: Larry McMurtry Brokeback Mountain
Answer: 2005