Microsoft Corp MSFT.O and Apple Inc AAPL.O were among the biggest weights on the S&P 500 and Nasdaq. By Caroline Valetkevitch NEW YORK, June 10 (Reuters) - U.S. stocks ended down sharply on Friday and posted their biggest weekly percentage declines since January as a steeper-than-expected rise in U.S. consumer prices in May fueled investor worries about more aggressive interest rate hikes by the Federal Reserve. Stocks have been volatile this year, and recent selling has largely been tied to uncertainty over the outlook for inflation and interest rates.