Respuesta :

Timings given by

  • 2:31
  • 3:13
  • 3:55
  • 4:37

Find sum

  • 2:31=2+3+1=6
  • 3:13=3+1+3=7
  • 3:55=3+5+5=13
  • 4:37=4+3+7=14

The next watch should show the time whose sum is 14+1=15

Coming to 1st watch

  • 5:19=5+1+9=15

Hence option A is correct

Spare way

Although there is another way .

We can observe that each timings are 42mins ahead from before.

Hence

Last time would be 4:37+0:42=5:19