Multiple choice

The sound signal carried by telephone line is

  1. rendomised

  2. digital

  3. analog

  4. customised

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Traditional telephone lines (POTS) carry analog voice signals. The sound waves are converted to continuous electrical signals that vary in amplitude and frequency. Digital telephony came later with technologies like ISDN and VoIP. Note option A contains a typo.