The correct answer is: D) The author carefully avoids using words that are too high level.
In few words, diction is a writer's choice of words. In this way the author defines his/her style of speaking or writing. By choosing the correct words, the reader can be persuaded or an effect can be made upon him. In this case, the text seems addressed to an unspecialized audience, if he uses high level words, the probabilities they undestand the main point decrease. A good writer knows wich words to choose depending the objective.
