Question: Which writer was of German descent, Herbert Achternbusch or Pedro Sienna?

Context paragraphs:
The Ghost (1982 film): The Ghost (German: "Das Gespenst" ) is a 1982 West German drama film directed by and starring Herbert Achternbusch.  It was entered into the 33rd Berlin International Film Festival.

Fred Bachrach: Albert Gustave Herbert "Fred" Bachrach, CBE (9 December 1914 – 18 December 2009) was a Dutch literary and art historian of French and German descent whose academic work featured in a number of prominent exhibitions and research works in Britain and the Netherlands and who founded the Sir Thomas Browne Institute for the study of Anglo-Dutch relations at Leiden University.  Bachrach had also served in the Dutch Army during the Second World War and spent three years as a Japanese prisoner of war, suffering starvation, torture, and deprivation that haunted him for the rest of his life.

Pedro Sienna: Pedro Sienna (13 May 1893—20 March 1972) was a Chilean playwright, poet, journalist, art critic and theatre and movie actor who is also remembered as one of his country's pioneering directors in the early years of silent film.

Heart of Glass (film): Heart of Glass (German: Herz aus Glas ) is a 1976 German film directed and produced by Werner Herzog, set in 18th century Bavaria.  The film was written by Herzog, based partly on a story by Herbert Achternbusch.  The main character is "Hias," based on the legendary Bavarian prophet Mühlhiasl.

Der Neger Erwin: Der Neger Erwin is a 1981 West German film directed by and starring Herbert Achternbusch.  It was entered into the 31st Berlin International Film Festival.

Wohin?: Wohin?  is a 1988 German drama film directed by Herbert Achternbusch.  It was entered into the 38th Berlin International Film Festival.

El Húsar de la Muerte: El Húsar de la Muerte (Spanish: "The Hussar of the Death" ) is a 1925 Chilean silent film movie.  "El Húsar de la Muerte" was directed and starred by Pedro Sienna.

Cândido Godói: Cândido Godói is a municipality of 6,641 inhabitants in the state of Rio Grande do Sul, Brazil near the Argentine border, famous for the high number of twins born there.  The twin phenomenon is centered in Linha São Pedro, a small settlement in the city of Cândido Godói, in an ethnically homogeneous population of German descent.

Hades (film): Hades is a 1995 German drama film directed by and starring Herbert Achternbusch.  It was entered into the 45th Berlin International Film Festival.

Herbert Achternbusch: Herbert Achternbusch (born 23 November 1938 in Munich) is a German writer, painter and filmmaker.  His anarchist surrealistic films are not known to a wide audience in Germany, although one of them, "Das Gespenst (The Ghost)", caused a scandal in 1983 because of its

Supporting paragraphs: Herbert Achternbusch Pedro Sienna
Answer: Herbert Achternbusch