（读写文件）下面代码采用缓冲的方式实现了将一个文件的内容复制到另一个文件的功能，下划线处应填写的代码是________。import java.io.*;public class Test {public static void main(String [] args){ try{ FileInputStream is = new FileInputStream(“D:\\from.txt”); FileOutputStream os =new FileOutputStream(“D:\\to.txt”); BufferedInputStream bi = new _________________(is); BufferedOutputStream bo = new BufferedOutputStream(os); byte[] data = new byte[1]; while(bi.read(data) != -1){ bo.___________(data); } bo.flush(); bi.close(); bo.close();}catch(ArrayIndexOutofBoundsException e){ e.printStackTrace();} catch(IOException e){ e.printStackTrace();} }} A、Buffered OutputStream,read B、BufferedInputStream，write C、BufferedInputStream，read D、BufferedOutputStream，write