What are the two major less-than-lethal weapons developed for law enforcement?
There have been many less than lethal weapons that have been used and are being used by police officers in the United States. These have ranged from simple night sticks to rubber bullets. It is not clear which two of these sorts of weapons you are being asked to identify. However, I would argue that the most likely answers to this question are pepper spray and weapons like Tasers. These are the non-lethal weapons that are both new and are used on a fairly regular basis by rank and file police officers.
Pepper spray and weapons like Tasers are widely used by police today. They are effective for controlling people who are violent or unwilling to obey police orders. They are much less likely to lead to serious injury than things like guns or even batons/night sticks are.
I would say that the best answer to this, then, is pepper spray and Tasers.