为自己加油

以下不能正确创建输出文件对象并使其与磁盘文件相关联的语句是

A.ofstream myfile; myfile.open("d:ofile.txt");
B.ofstream *myfile=new ofstream; myfile->open(d:ofile.txt");
C.ofstream myfile.open("d: ofile.txt");
D.ofstream *myfile=new("d:ofile.txt");