Complex sentence: The second possible element of an office action are actual basis for rejection of the mark itself, the most frequent being likelihood of confusion with an existing registered mark and genericness or descriptiveness of the mark for which registration is sought.
Split into simpler sentences: The second possible element of an office action is an actual basis for rejection of the mark itself. The most frequent bases are likelihood of confusion with an existing registered mark and genericness or descriptiveness of the mark for which registration is sought.