By Caroline Valetkevitch NEW YORK (Reuters) – U.S. stocks sold off sharply Thursday as investor anxiety heightened ahead of data on Friday that is expected to show consumer prices remained elevated in May. Selling picked up toward the end of the session. Mega-cap growth stocks led the drop, with Apple Inc and Amazon.com Inc falling 3.6% and 4.2%, respectively, and putting the most pressure on the S&P 500 and the Nasdaq. Communication services and technology had the biggest declines among sectors, although all 11 S&P 500 sectors ended lower on the day. Adding to nervousness, the benchmark U.S. …