The word "kindle" means to start a fire, ignite, or arouse. It is often used metaphorically to describe the act of sparking or igniting something, such as an emotion or a passion. In this context, "kindle" is the correct answer because it best aligns with the given definition. The other options, "tout," "brawn," "efface," and "obscure," do not have the same meaning or association with starting a fire or igniting something.