A Digital Clock Model Decodes a 1 Pulse Per Second

Multiple Choice

A digital clock model decodes a 1 pulse per second input into seconds, minutes and hours; sixty seconds advance minutes, and sixty minutes advance hours. How do hours recycle back to one after 12?

A) The 1 for tens of hours and 2 for ones of hours is detected and resets hours back to zero.
B) The 2 is detected and resets the new tens and ones of hours to zero.
C) A MOD 6 counter automatically resets hours to zero.
D) The 1 for tens of hours and 2 for ones of hours is detected and resets hours back to 1 o'clock.