The correct answer is Improves analytical query speed by reading only the columns that are needed.

Columnar storage organizes data by column so queries only need to scan the specific columns they reference. This reduces the amount of data read from disk and lowers I/O overhead which makes analytical queries that aggregate or filter on a subset of columns much faster.

Reduces storage costs through higher compression rates is not the best choice because higher compression can be a side benefit of columnar formats but the primary performance gain for analytics comes from reading fewer columns rather than from storage cost savings.

Provides stronger controls for protecting sensitive fields is incorrect because access control and data protection are provided by the database or platform features rather than by the columnar layout itself. Column organization by itself does not enforce stronger security controls.

Increases the speed of ingesting data from many sources is wrong because columnar formats often favor read and compression efficiency and they may require batch or transformation steps during ingestion. Ingest performance depends more on the ingestion pipeline and tooling than on using a columnar format.

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