Sarah is leading a class of 35 students. Initially, all students are standing. Each time Sarah waves her hands, a prime number of standing students sit down. If no one is left standing after Sarah waves her hands 3 times, what is the greatest possible number of students that could have been standing before her third wave?
<spanclass=′latex−bold′>(A)</span>23<spanclass=′latex−bold′>(B)</span>27<spanclass=′latex−bold′>(C)</span>29<spanclass=′latex−bold′>(D)</span>31<spanclass=′latex−bold′>(E)</span>33