What sets NoSQL databases apart from traditional SQL databases?

NoSQL databases are distinguished by their ability to handle unstructured data and provide flexible data models, which is a significant departure from the constraints of traditional SQL databases. SQL databases are primarily built on a structured framework; they require data to fit into predefined schemas, which can limit the types of data you can store as well as how it can be queried.

In contrast, NoSQL databases are designed to accommodate a variety of data types, including semi-structured and unstructured data such as documents, key-value pairs, and graphs. This flexibility allows developers to work with data in a more dynamic manner, making it easier to handle changes in requirements and to manage large volumes of diverse data. Additionally, NoSQL databases can scale horizontally, which facilitates handling large sets of data efficiently.

This adaptability is why option C captures the essence of what sets NoSQL databases apart from their SQL counterparts, recognizing the importance of unstructured data and the advantage of flexible data models.