PubNub publishes and subscribes . . . . . . . . in order to send and receive messages.

The correct answer is: channels.

PubNub is a real-time data streaming platform that allows you to publish and subscribe to channels in order to send and receive messages. A channel is a logical grouping of messages that are related to a specific topic. When you publish a message to a channel, all subscribers to that channel will receive the message. When you subscribe to a channel, you will receive all messages that are published to that channel.

The other options are incorrect because:

• A network is a group of
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