通过Intent来调用系统的拨号程序，代码应该是\n
A、Uri uri = Uri.parse("tel:13566667777");
Intent it = new Intent(Intent.ACTION_DIAL, uri);  
startActivity(it);
B、Uri uri = Uri.parse("tel:13566667777");
Intent it = new Intent(Intent.ACTION_DIAL);
 startActivity(it);
C、 Uri uri = Uri.parse("tel:13566667777");
Intent it = new Intent(uri);  
startActivity(it);
D、Intent it = new Intent(Intent.ACTION_DIAL);  
startActivity(it);