Answer choice (B) is incorrect because it is too strong. Rotelle does not say that people as old as or older than Sims are the only people who cannot effectively address the difficult issues facing the country. It is entirely possible that Rotelle believes people younger than a certain age are also incapable of addressing these issues.
However, Rotelle does commit to the conclusion in (D). We know that Rotelle believes that Sims is too old to effectively address the country's issues. Therefore, someone who is effectively able to address these issues must at least be younger than Sims.
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