Question

Persuading a peace activist to support a war involves:

Answer 1

A.
A peace activist is against war, so you would have to change their beliefs to have the support war.

Answer 2

That would be changing beliefs. because motivating a peace activist to action would mean motivating them to protest peace.
weakening their attitude would result in a sedentary and apathetic response. and strengthening their values would be making them even more of a pacifist. therefore you most change their beliefs before you go forth with any of the other options.
hope this helps!