Final answer:
The DSL type that uses 3 FDM channels with different channels for voice, downstream, and upstream data is ADSL (Asymmetric Digital Subscriber Line).
Step-by-step explanation:
The type of DSL that uses 3 FDM channels, including a 4KHz analog voice channel for regular telephone service, a simplex data channel for downstream traffic, and a slower full-duplex data channel for upstream traffic, is known as ADSL (Asymmetric Digital Subscriber Line).
ADSL is designed to provide faster download speeds compared to upload speeds, which is reflective of most users' internet behavior—where downloading data is more frequent than uploading. The term 'asymmetric' refers to this difference in speed. This type of DSL is tailored for residential users, where the demand for high-speed internet access is high for activities such as streaming videos, online gaming, and downloading files.