The correct answer is: B. Internet of Things
MQTT (Message Queuing Telemetry Transport) is a lightweight publish/subscribe messaging protocol. It is designed for connections with remote devices with resource constraints and is ideal for connecting devices to the cloud. MQTT is one of the most popular protocols for the Internet of Things (IoT).
A. Machine to machine (M2M) is a type of communication between two or more machines without human intervention. M2M communication is often used in industrial automation, logistics, and healthcare.
C. Machine to machine and internet of things (M2M and IoT) is a combination of M2M and IoT. M2M and IoT are often used interchangeably, but there is a subtle difference between the two. M2M is a type of communication, while IoT is a network of devices.
D. Machine things is not a valid option.