Final answer:
The correct answer is to start the left turn from the leftmost lane on a multi-lane one-way road when turning onto another one-way road to ensure safety and compliance with traffic laws. So, the correct answer is 1) The leftmost lane.
Step-by-step explanation:
When turning left from a multi-lane one-way road onto another one-way road, you should start your turn from the leftmost lane.
Turning from any other lane could lead to a traffic violation and increases the risk of a collision.
Typically, traffic rules are designed to keep traffic flowing smoothly and safely, so it's essential to follow the proper procedures for lane usage when making turns.
Thus, the correct answer is 1) The leftmost lane.