道路两边的标识牌如图所示，它指的是？The signs on both sides of the road as shown in the picture are referring to? Which one is it referring to?
最低时速60公里Minimum speed 60 kilometers per hour
最高时速60公里Maximum speed 60 kilometers per hour
只有天气不好的时候，才限速60公里Limiting to 60 kilometers per hour only when the weather is bad