Answer:
D.
Step-by-step explanation:
The state may ban the radar detectors. States may regulate local aspects of interstate commerce as long as the local regulation does not conflic with, or is not preempted by, federal regulation and the regulation meet:
The regulation does not discriminate against out-of-state competition in order to benefit local economic interest.
The incidental burden on interstate commerce does not outweight the local benefits of the regulation.