Final answer:
The melody of Schubert's Lied 'The Trout' is used in the quintet as a recurring theme.
Step-by-step explanation:
The melody of Schubert's Lied 'The Trout' is used in the quintet of the same name as a recurring theme.
Throughout the quintet, Schubert uses various transformations and developments of the 'The Trout' melody to create a cohesive musical structure. This melody is present in all five movements of the quintet and serves as a unifying element.
For example, in the fourth movement of the quintet, Schubert takes the main theme of 'The Trout' and incorporates it into a set of variations, showcasing different musical treatments and variations of the melody.