The answer is ..."all of the above" are required.
By reading the section "b" part that says...
(B) is used only for exhibitions, club activities, parades, and other functions of public interest and not for regular transportation;
and
I bolded that word "and" ...this links all three together. Gotta have the insurance. You need fed minimum liability insurance. You will get a cheaper rate on everything if you register it as an antique or classic vehicle.
Funny thing is...why was insurance not needed when we had Model A's & T's, Classic cars, etc. ? Same things happened then as they do now.
Maybe ask as well...why do we need to ask for permission (permit/driver's license) to drive or travel on the roads our money built? Aren't we all supposed to be free to travel within our country (USA) without hindrance? But I'll leave the rest to another forum where American History and natural rights are discussed.