Considering the tone and the message in the excerpt, I believe the correct answer to be option C: "All people should dedicate a fair amount of their time to politics", this is because of the way Roosevelt says that everyone has a civic duty and there is no excuse that justifies not fulfilling said duty. He also says that voting is the least a person could do and by doing so, is not to be regarded as a "good citizen" since they could be doing more. So basically, it isn't option A or B or D, especially this last one since he condemns people who vote not just those who do not vote.
What Theodore Roosevelt claims in the excerpt is that All people should dedicate a fair amount of their time to politics.
Explanation:
This excerpt from the speech of Theodore Roosevelt talks about the moral duty that every citizen has in order to be part of a free society, he makes a call to the conscience of each and every one of the American people about the effort that has to be done to keep on living with the freedom they now enjoy and that people need to work together in political terms to make their liberty prevail.