While driving on a roadway with a single broken white centerline:

1. You must stay within your lane.
2. You may cross the centerline to change lanes. ✓
3. You may change lanes only from the left lane.

Answer: B. You may cross the centerline to change lanes.

You may cross the single broken white line to change lanes.

Why this is the answer

The handbook describes broken white lines as dividers between traffic lanes on roads with two or more lanes going the same direction. In the same section, it tells drivers never to change lanes over double solid white lines and to wait until a single broken white line appears. That makes the single broken white line the marking that allows a lane change, so crossing it to move into another lane fits the handbook. It is not a barrier like the double solid white lines.

Why the other answers are wrong

• A. You must stay within your lane. — A single broken white line is not a stay-in-lane barrier; the handbook uses it as the point where a lane change over white lines is allowed.
• C. You may change lanes only from the left lane. — The passages give no left-lane-only rule for changing lanes; the broken white line itself is what permits the move between same-direction lanes.

Remember it

Remember it this way: double solid white is the closed door, and the single broken white line is the opening you wait for.