下列程序将类C15的对象写入文件filetxt，选择正确的语句填入下列程序的横线处。 package ch2; import javA.util.*; import javA.io.*; class C15______ { public iht a; public void setInt(int newa) { a = newa; } } public class Testl5 { pulibc static void main(String[] args) { C15 bj = new C15(); try { FileOutputStream fos =newFileOutputStream('ch2//filel5.txt'); ObjectOutputStream os = ObjectOutputStream(fos); Obj.setInt(10); oos.writeObject(obj); oos.close (); fos.close(); } catch(IOException ioe) { ioE.printStackTrace(); } } }
A.implements Runnable
B.implements Sedalizable
C.extends Serializable
D.implements InputStream