The auxiliary steering gear must be capable of being brought speedily into operation and be able to put the rudder over from 15 degrees on one side to 15 degrees on the other side in no more than （） with the ship at its deepest service draught and running ahead at the greater of one half of the maximum service speed or （）.

A. 28 seconds；7 knots
B. 28 seconds；14 knots
C. 60 seconds；7 knots
D. 60 seconds；14 knot