A group of students in your school communicate via Skype to complete an assignment. Which of the following enables them to hear each other using Skype?

The technology that enables students to hear each other using Skype is called Voice over Internet Protocol (VoIP). Here are the steps explaining how it works:

1. Voice Input: When a student speaks into their microphone, the analog sound waves of their voice are converted into digital data by the computer's sound card.

2. Data Compression: The digital data is then compressed to make it smaller and easier to transmit over the internet. This is done by the Skype software.

3. Data Transmission: The compressed digital data is sent over the internet from the sender's computer to the receiver's computer. This is done using the internet connection of both computers.

4. Data Decompression: The received digital data is decompressed back into its original form by the Skype software on the receiver's computer.

5. Voice Output: The decompressed digital data is converted back into analog sound waves by the receiver's sound card and output through their speakers or headphones. This allows the receiver to hear the sender's voice.

So, the combination of hardware (microphone, sound card, speakers or headphones) and software (Skype, which uses VoIP technology) enables the students to hear each other using Skype.