What typically differentiates extremists from radicals?

The distinction between extremists and radicals largely hinges on their approach to reform. Extremists often advocate for drastic measures or violence to achieve their objectives, rejecting the established norms and methods of change that are typically seen as legitimate within society. In contrast, radicals may seek significant change or reform within the current societal framework but do not necessarily resort to extreme measures. They are often engaged in dialogue and seek to bring about change through activism or political processes, even if their goals are fundamentally transformative. This fundamental difference in their strategies and methods is what clearly sets them apart, making the chosen answer accurate.

The other options, such as interpretation of doctrine, acceptance of societal norms, and influence on cultural issues, may have some relevance but do not capture the core distinction in their approach to enacting change as effectively as the correct answer does.