Recall, 24 hours = 1 day
Thus, a day and half is 24 + 24/2 = 36 hours
If we subtract 24 hours which is a day from 3:15am, we would arrive at 3:15 am
If we subtract 12 hours from 3:15 am, we would arrive at 3:15 pm
Subtracting the remaining 1 hour from 3:15pm, we would arrive at 2:15 PM
Thus, the correct option is C