What does a solid double yellow line mean?

Answer: C — No passing is allowed in either direction

A solid double yellow line serves as a critical visual signal on the roadway, indicating that no passing is allowed in either direction. This rule is in place to enhance safety for all road users, particularly in areas where visibility is limited or where the road conditions may make passing hazardous. The solid lines are a clear indication that crossing them to overtake another vehicle poses a significant risk, and thus driver compliance is essential to prevent accidents. While there may be other markings or signs that suggest specific changes, such as those indicating allowable passing or speed limits, a solid double yellow line clearly denotes a prohibition against passing. This means that drivers must remain in their lane, emphasizing the importance of maintaining safe distances and respecting other vehicles on the road.