The correct answer is To accelerate query performance by building a structure for fast lookups.

Indexing creates auxiliary data structures that let the system locate records without scanning the entire dataset and that reduce query latency for targeted lookups and range queries. Building an index often involves tree or hash structures that optimize search operations and that trade increased storage use and slower writes for much faster read performance.

To create redundant copies of data for disaster recovery is incorrect because making redundant copies is achieved with replication, backups, and snapshots and not with an index.

To secure stored information by applying encryption at rest is incorrect because encryption protects data confidentiality and is implemented by storage encryption settings rather than by indexing.

To reduce the storage footprint by compressing data is incorrect because compression reduces disk usage while indexing usually increases storage overhead to support faster lookups.

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