Question: Among David Bowers and John G. Adolfiwho was an American silent film director?
Context: Clifford Sanford Elfelt (Chicago, Illinois, December 13, 1892 – Los Angeles, California, September 3, 1975) was an American silent film director, writer and producer.  He was active in the silent film industry from 1916 up to 1926, worked with Universal Studios, was head of Metropolitan Pictures Corporation of California and had his own Clifford S. Elfelt Productions company.  He was married to the actress Gladys E. Fry (1903 - 1991, also known as June LaVere), who divorced him in 1923. The Wonder Man is a 1920 American silent film directed by John G. Adolfi and starring Georges Carpentier. Day at the Circus is a 1901 American silent film produced and distributed by Edison Manufacturing Company and directed by Edwin S. Porter.  It depicts a parade of the Great Forepaugh and Sells Bros.  Combined Circus followed by a horse race in the tent.  It was one of many early silent film documentaries depicting circuses, which historian Katherine H. Adams said, "The circus' emphasis on movement and quick transition, as well as its lack of dialogue, made it a perfect subject matter for silent film." John Gustav Adolfi (February 19, 1888 – May 11, 1933) was an American silent film director, actor, and screenwriter who was involved in more than 100 productions throughout his career.  An early acting credit was in the recently restored 1912 film "Robin Hood". Le Giornate del cinema muto (referred to in English as Pordenone Silent Film Festival) is an annual festival of silent film held in October in Pordenone, northern Italy.  It is the first, largest and most important international festival dedicated to silent film and also is present in the list of the top 50 unmissable film festivals in the world according to Variety.  The Pordenone Silent Film Festival is a non-profit association, whose president is Livio Jacob.  The director from 1997 until 2015 was David Robinson.  Other members of the festival board are Paolo Cherchi Usai, Lorenzo Codelli, Piero Colussi, Luciano De Giusti, Carlo Montanaro, Piera Patat. What Every Woman Knows is a 1921 American silent comedy drama film adapted form the play "What Every Woman Knows" by James Barrie.  The play had premiered on Broadway in 1908 and was a hit starring Maude Adams.  A British silent film version had been made in 1917 and a later American talkie would be produced in 1934 with Helen Hayes.  This silent film version was directed by William C. deMille continuing his forte at adapting literary and/or stage plays to the silent screen.  The film stars Lois Wilson and Conrad Nagel.  This version is now lost. Michael G. Ankerich is a biographer whose work focuses on American silent film and early twentieth century actors and actresses.  Ankerich's interviews with the last remaining silent film stars were featured in "Broken Silence: Conversations With 23 Silent Film Stars" (1993) and "The Sound of Silence: Conversations with 16 Film and Stage Personalities Who Made the Transition from Silents to Talkies" (1998).  His biography of silent film actress Mae Murray, "Mae Murray: The Girl with the Bee-Stung Lips," was named one of the top 10 must-read film books of 2012. Tol'able David is a 1930 American sound drama film directed by John G. Blystone and produced and released by Columbia Pictures.  It is a remake of a famous 1921 silent film "Tol'able David" starring Richard Barthelmess and Ernest Torrence.  This Columbia film stars newcomer Richard Cromwell in the Barthelmess part after he won an audition over thousands of hopefuls and Harry Cohn gave him his screen name and a $75/week contract.  It is preserved in the Library of Congress. David Bowers (born 1970) is an English animator, film director, screenwriter and voice actor originally from Stockport, Greater Manchester in the UK. Dick Turpin is a 1925 American silent film and historical adventure directed by John G. Blystone produced and distributed by Fox Film Corporation and starring western hero Tom Mix.  Mix departs from his usual western roles to play a British historical figure, the highwayman Dick Turpin (1705-1739).  A young Carole Lombard was filmed in several scenes which mostly ended up on the cutting room floor.
Answer: John Gustav Adolfi