Per 46 CFR §58.25-10, the main steering gear 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, with the vessel at deepest loadline draft and running at maximum ahead service speed?

Why C is correct

46 CFR §58.25-10(c)(2) specifies that the main steering gear must 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 requirement applies to the auxiliary steering gear for a lesser rudder angle movement.