27. In the diagram, if the motorcyclist X intends to turn left, what is the safest way?
(A) Turn on the left turn signal 10 m before the intersection, change to the fast lane, and travel to the center of the intersection, and turn left after making sure there is no oncoming traffic. (B) Turn on the left turn signal 30 m before the intersection and change to the fast lane, and travel to the center of the intersection, and turn left after making sure there is no oncoming traffic. (C) Change to the fast lane directly and turn left upon passing the stop-line.