When daylight savings time is kept,the time of tide and current calculations must be adjusted.One way of doing this is to ().
A.
Add one hour to the times listed under the reference stations
B.
Subtract one hour from the time differences listed for the subordinate stations
C.
Apply no correction as the times in the reference stations are adjusted for daylight savings time
D.
Add 15° to the standard meridian when calculating the time difference