The correct answer is Internet of Things.

A bedside lamp you power on from a smartphone fits the Internet of Things because it is a physical device that is network connected and can be controlled remotely by an application. IoT describes devices that combine hardware, connectivity, and software to enable monitoring, control, or automation, which is exactly what a smart lamp demonstrates.

Machine learning is incorrect because it refers to algorithms that learn patterns from data. A simple remotely controlled lamp does not need learning models to operate.

Artificial intelligence is incorrect because it denotes systems that exhibit intelligent or autonomous behavior. A lamp that only turns on or off when commanded by an app does not necessarily perform intelligent decision making.

Cryptography is incorrect because it is the practice of securing information and communications. While cryptography may be used to protect commands or data for a smart lamp it does not describe the category of the device itself.

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