Which of the following is the BEST solution for storing both non-relational and relational personal data from Internet of Things (IoT) devices, web sites, and mobile applications?

A data lake stores data in its raw, native format - structured (relational tables), semi-structured (JSON, XML), and unstructured (logs, sensor streams, media) - making it ideal for ingesting heterogeneous data from IoT devices, web applications, and mobile apps simultaneously. It scales to handle the high velocity and volume typical of these sources without requiring data transformation at ingestion time. No other listed option natively handles both relational and non-relational data from multiple concurrent source types.

Block storage is a low-level infrastructure storage mechanism (such as virtual disks) used to provide raw storage capacity; it has no built-in capability for organizing, querying, or managing relational or non-relational data from multiple application sources.

Blockchain is a distributed ledger technology designed for immutable transaction recording and verification, not for general-purpose storage or querying of diverse personal data from IoT and web sources.

A data warehouse is optimized for structured, relational data organized into schemas for analytical querying; it does not natively handle the non-relational, semi-structured, or raw formats produced by IoT devices and mobile applications.