The correct option is this: IT CONNECTS WORDS, PHRASES, OR SENTENCES RELEVANT TO THE MAIN TOPIC.
Brain storming is one of the method use in pre-writing. The method involves forcing one natural thinking process to think in order to get creative ideas that has to do with a particular topic. When one is free writing, one should allow his or her thoughts to flow freely and then write down on paper all that come into one's mind in relation to one's main topic. At this stage, one does not have to bother himself about spellings, punctuation, structure, grammar, etc.