The correct answer is D. Sixteen.
IS-136 is a digital cellular telecommunications standard developed by the Telecommunications Industry Association (TIA). It is also known as Digital AMPS (D-AMPS) or North American TDMA. IS-136 uses a time division multiple access (TDMA) scheme to divide each 30 kHz radio channel into six time slots. This allows for a total of 16 voice channels to be supported on each 30 kHz radio channel.
Option A is incorrect because it states that eight voice channels are supported for each 30 kHz radio channel. This is not the case, as IS-136 supports 16 voice channels per 30 kHz radio channel.
Option B is incorrect because it states that thirty voice channels are supported for each 30 kHz radio channel. This is not the case, as IS-136 supports 16 voice channels per 30 kHz radio channel.
Option C is incorrect because it states that three voice channels are supported for each 30 kHz radio channel. This is not the case, as IS-136 supports 16 voice channels per 30 kHz radio channel.