The correct option is B 12:25 pm
Time at which first bus departs
= 10:25 am
Converting this to the time in the 24-hour format, we get 10:25.
Since buses leave every 2 hours, the next bus leaves at 10:25 + 02:00 = 12:25(in the 24-hour format), which is same as 12:25 pm.
[pm is used to describe the second portion of the day, starting from noon right after 12 to just before 12 midnight.]