What does data integrity ensure in the context of information security?

Data integrity is a fundamental principle in information security that focuses on maintaining the accuracy and consistency of information over its entire life cycle. This means that data should remain unaltered and reliable when it is stored, processed, or transmitted, ensuring that it reflects a true and accurate representation of the original input. For example, data integrity measures may include checksums, hashing, and validation processes that detect and prevent unauthorized modifications or errors. Maintaining data integrity is crucial for organizations relying on accurate data for decision-making and operations, as any inconsistency can lead to erroneous interpretations and potentially harmful consequences.

In contrast to the other options, while protection against insider threats is a significant security concern, it does not specifically relate to data integrity itself. Fast retrieval of data relates more to performance and efficiency, not to its accuracy or consistency. The absence of data redundancy pertains to data management rather than the integrity of that data. Thus, the focus of data integrity is squarely on ensuring that information remains accurate and consistent, which is why it is the correct answer.