Question: Who, Robert Mulligan or Ruby Yang, is a Chinese American filmmaker?
Context: Ruby Yang (楊紫燁; Simplified Chinese: 杨紫烨), is a Chinese American filmmaker. Estelle Hemsley (May 5, 1887 - November 5, 1968) was a prominent early African American actress of stage and screen.  She appeared in the stage and screen versions of "Take a Giant Step", earning a Golden Globe nomination for Best Supporting Actress in the 1959 movie directed by Philip Leacock.  Her other notable film roles include playing Grandmother Topouzoglou in Elia Kazan's 1963 movie "America, America" (nominated for the Oscar for Best Picture), the role of Cla-Cla in Mel Ferrer's 1959 film "Green Mansions", the mother of Ruby Dee in "Edge of the City" (1957), and Catherine in Robert Mulligan's 1965 movie "Baby the Rain Must Fall". My Voice, My Life 《爭氣》is a feature-length documentary film directed by Oscar-winning Chinese-American filmmaker Ruby Yang.  It tells the poignant stories of a group of under-privileged Hong Kong youngsters who underwent six months of vigorous trainings to produce a musical on stage.  Through their trials and tribulations, the students challenge parents, teachers and policy makers to reflect on our way of nurturing the next generation. Chung Tao Yang, or Chung-Tao Yang, Yang Zhongdao (Traditional Chinese: 楊忠道, Simplified Chinese: 杨忠道, Pinyin: Yáng Zhòngdào) (May 4, 1923 – 2005), was a notable Chinese American topologist.  He was an academician of the Academia Sinica and served as the chair of the Department of Mathematics, University of Pennsylvania. Richard Mulligan (November 13, 1932 – September 26, 2000) was an American television, film and character actor known for his role as Burt Campbell, the loving, preventive husband of Cathryn Damon's character, in the sitcom "Soap" (1977–81) and later for his starring role as Dr. Harry Weston in "Empty Nest" (1988–95).  He was the younger brother of film director Robert Mulligan. Robert Patrick Mulligan (August 23, 1925 – December 20, 2008) was an American film and television director best known as the director of humanistic American dramas, including "To Kill a Mockingbird" (1962), "Summer of '42" (1971), "The Other" (1972), "Same Time, Next Year" (1978) and "The Man in the Moon" (1991).  He was also known in the 1960s for his extensive collaborations with producer Alan J. Pakula.  He was the elder brother of actor Richard Mulligan. As of 2012, 21.4% of the population in San Francisco was of Chinese descent, and at least 150,000 Chinese American residents.  The Chinese are the largest Asian American subgroup in San Francisco.  San Francisco has the highest percentage of residents of Chinese descent of any major U.S. city, and the second largest Chinese American population, after New York City.  The San Francisco Bay Area is 7.9% Chinese American, with many residents in Oakland and Santa Clara County.  San Francisco's Chinese community has ancestry mainly from Guangdong province, China and Hong Kong, although there is a sizable population of ethnic Chinese with ancestry from other parts of mainland China and Taiwan as well. The Rat Race is a 1960 American drama film directed by Robert Mulligan and starring Tony Curtis and Debbie Reynolds as struggling young entertainment professionals in New York City.  Filming took place in Pittsburgh, Pennsylvania.  Sam Butera and Gerry Mulligan have minor roles as saxophonists. The Organization of Chinese American Women (abbreviated as OCAW) is a national nonprofit, nonpartisan organization dedicated to advancing the interests of Chinese American women in the United States and increasing awareness of issues affecting them.  It was founded in 1977 by Pauline Tsui, and is headquartered in Washington, D.C.  At first it was affiliated with the Organization of Chinese Americans, but it was regarded as an auxiliary rather than an equal partner, and the two groups had different priorities, so they broke apart in 1987.  In contrast to the Organization of Chinese Americans, which is mainly a political advocacy group, the Organization of Chinese American Women primarily provides services and assistance to its members.  It is supported by membership, private donations and public grants.  Its mission statement reads "To advance and to advocate for the needs and concerns of Chinese and other Asian Pacific American women by helping to improve their educational, economic, social, and political opportunities, and by recognizing their excellence, leadership, and contributions to the quality of life." The Warriors of Qiugang () is a 39-minute documentary film that chronicles the story of the Chinese village of Qiugang (pop.  1,900 in "ca."  2010), in the suburbs of Bengbu City in Anhui Province in central-eastern China.  It tells how a group of Chinese villagers put an end to the poisoning of their land and water by three chemical plants, the worst being Jiucailuo Chemical.  It was directed and produced by Academy Award winners Ruby Yang and Thomas F. Lennon, respectively.  Guan Xin was the field producer and cinematographer.
Answer: Ruby Yang