Article 69 of Bahrain's Traffic Law Implementing Regulation states the lane rule for drivers of heavy transport vehicles. How is it framed?

1. They must use the leftmost lane so slower traffic is not held up
2. They must keep to the right-hand lane of the carriageway in all cases, and may not overtake unless the condition of the road or their destination requires it
3. They may use any lane provided they signal each change
4. The rule applies only on roads with three or more lanes