What is the restriction of crossing double solid white lines?

Crossing double solid white lines is not permitted because these lines indicate a lane separation where lane changes are discouraged for safety reasons. The purpose of double solid white lines is to indicate that staying in your lane is crucial due to either limited visibility, the presence of fixed objects, or other hazards. This restriction helps to maintain traffic flow and reduces the likelihood of accidents caused by unexpected lane changes in these areas.

The other options suggest conditions under which crossing these lines might be acceptable; however, the law clearly prohibits it to ensure the safety of all road users. Always maintaining a clear understanding of lane markings and adhering to them is vital for safe driving practices.