Please answer the following question: Read the following paragraph and extract the answer for the question: What is the name of the first piece Saint-Saens acknowledged as a mature work? In 1848, at the age of thirteen, Saint-Saens was admitted to the Paris Conservatoire, France's foremost music academy. The director, Daniel Auber, had succeeded Luigi Cherubini in 1842, and brought a more relaxed regime than that of his martinet predecessor, though the curriculum remained conservative. Students, even outstanding pianists like Saint-Saens, were encouraged to specialise in organ studies, because a career as a church organist was seen to offer more opportunities than that of a solo pianist. His organ professor was Francois Benoist, whom Saint-Saens considered a mediocre organist but a first-rate teacher; his pupils included Adolphe Adam, Cesar Franck, Charles Alkan, Louis Lefebure-Wely and Georges Bizet. In 1851 Saint-Saens won the Conservatoire's top prize for organists, and in the same year he began formal composition studies. His professor was a protege of Cherubini, Fromental Halevy, whose pupils included Charles Gounod and Bizet.Saint-Saens's student compositions included a symphony in A major (1850) and a choral piece, Les Djinns (1850), after an eponymous poem by Victor Hugo. He competed for France's premier musical award, the Prix de Rome, in 1852 but was unsuccessful. Auber believed that the prize should have gone to Saint-Saens, considering him to have more promise than the winner, Leonce Cohen, who made little mark during the rest of his career. In the same year Saint-Saens had greater success in a competition organised by the Societe Sainte-Cecile, Paris, with his Ode a Sainte-Cecile, for which the judges unanimously voted him the first prize. The first piece the composer acknowledged as a mature work and gave an opus number was Trois Morceaux for harmonium (1852).
Answer:
Trois Morceaux for harmonium