Asynchronous I/O Available to Windows XP Threads Can Be Managed

Asynchronous I/O available to Windows XP threads can be managed by ________.

A) issuing the I/O request, performing some other processing and waiting on an event object to signal the completion of the I/O
B) performing alertable I/O, in which case a thread issues the I/O request, performs some other processing and then enters an alertable wait state to process an APC associated with the I/O completion
C) using an I/O completion port, enabling another thread that registered with the port and that is waiting for I/O completion packets to process them
D) all of the above.