How did Bach's cantatas primarily differ from Scarlatti's compositions?

Bach's cantatas are primarily noted for their sacred content, designed to be performed in religious settings, particularly in Lutheran worship services. These works not only served a liturgical purpose but also integrated theological themes, drawing on scripture and hymns, which provided spiritual nourishment to the congregation.

In contrast, Scarlatti's compositions, although he did write some vocal works, were not focused on the same sacred traditions. Instead, he was more renowned for his operas and keyboard sonatas, which often emphasized secular themes. This distinction in thematic focus highlights why option C is the correct answer, as it underscores Bach's commitment to religious expression through music, creating a unique space for sacred cantatas in the context of worship.

The other options do not accurately represent the primary differences in the nature of their compositions. The nature of Bach’s works as purely instrumental (the second choice) overlooks the vocal and choral elements crucial to his cantatas. Furthermore, while entertainment might play a role in some of Bach's work, labeling his cantatas as solely secular (the first choice) misrepresents their primary intention. Lastly, while it's true that Scarlatti's works varied in complexity, the statement regarding the length and complexity of his cantatas