In "TDD", what does the second "D" stand for?

In "TDD", what does the second "D" stand for?

• A. Deaf
• B. Dispatch
• C. Dedicated
• D. Device

Answer: (A)

The second D in TDD stands for Deaf. TDD is the Telecommunications Device for the Deaf, an assistive technology that enables text-based communication over telephone lines for people who are deaf or hard of hearing. The phrase signals who the device serves, not the function of the device itself. So the second D specifically identifies the user group—Deaf. The other options don’t fit the established meaning of that letter in this acronym. (If you were looking at the whole phrase, the first D would be Device, but the question asks about the second D.)

The second D in TDD stands for Deaf. TDD is the Telecommunications Device for the Deaf, an assistive technology that enables text-based communication over telephone lines for people who are deaf or hard of hearing. The phrase signals who the device serves, not the function of the device itself. So the second D specifically identifies the user group—Deaf. The other options don’t fit the established meaning of that letter in this acronym. (If you were looking at the whole phrase, the first D would be Device, but the question asks about the second D.)