In order to deal with Tone Questions in RC you need to look for expressions in the passage that might suggest the author's attitude. Also some expressions are often repeated so it is advisable to collect a few words from each RC Tone question and compile a list of the most common phrases. When you are going to write the words down - try to mark whether they appeared in the correct answer. You will see that some adjectives and adverbs are almost always used as distractors.