题目

阅读理解 The Peales were a famous family of American artists. Charles Willson Peale is best remembered for his portraits of leading figures of the American Revolution. He painted portraits of Franklin and Jefferson and over a dozen of George Washington. His life-size portrait of his sons Raphaelle and Titian was so realistic that George Washington reportedly once tipped his hat (脱帽打招呼) to the figures in the picture. Charles Willson Peale gave up painting in his middle age and devoted his life to the Peale museum, which he founded in Philadelphia. The world's first popular museum 8．下列函数中，在其定义域内，既是奇函数又是减函数的是（　　）A．f（x）=x3B．f（x）=$\sqrt{-x}$C．f（x）=2-x-2xD．f（x）=-lg|x|