In what ways do seat-belt laws vary among the states?

Explanation:

Belt use rates are higher in states with primary enforcement laws, which allow police to stop a driver solely for not using a seat belt. In states with secondary enforcement, police can only enforce the belt law if they have pulled over the driver for another violation first.

they keep you safe that is what I think and why aren’t on the buses

i believe the answer would be 'd'.

hope this !

answer; /// i believe its the cochlea;