Windows is very happy to run a program automatically when a USB flash drive is inserted into a PC . How convenient , both for end users and for bad guys .

Q with options: Give answer the following question using evidence from the above passage: Why would it be convenient for the bad guys ?
Options:
[A]. Because bad guys can fix viruses off the USB drive .;
[B]. None of the above choices .;
[C]. Because bad guys can install an antivirus of the USB drive .;
[D]. Because bad guys can run viruses off the USB drive .;
[D].