The main steering gear of a vessel at its deepest loadline draft and running at maximum ahead service speed must be capable of moving the rudder from 35° on either side to 30° on the other side in not more than how many seconds?

Why D is correct

46 CFR §58.25-10(c)(2) requires the main steering gear to move the rudder from 35° on either side to 30° on the other in not more than 28 seconds at deepest loadline draft and maximum ahead service speed. The 60-second figure applies to the auxiliary steering gear under different conditions.