The best restatement of kant's categorical imperative is:

The best restatement of kant's categorical imperative is:Do to others as you would have everyone do
Kant believed that humans are inclined to to be good to other people if we feel 'indebted' to that other people. So, he think that human have to constantly do good deeds to other people in order to gained more peers within a social group

Absolute !

Icould be wrong but i would say b.