Caitlin+C

I think the argument implied is that road workers want speed limits to be lowered for their safety and for the safety of others; they may have lost someone due to people driving too fast. The argument is also saying that everyone needs to slow down and the only way to get people to do that is to lower the speed limit. The opposite view would think that speed limits are what they are for a reason and that they don't need to be changed. The black and white makes the picture appeal to emotions.