Thomas Came into Work This Morning and Turned on His

Thomas came into work this morning and turned on his computer and nothing happened. He immediately called the help desk, and you were sent to fix his computer. While talking with Thomas about his computer, you find out that when he turns on the computer, he has lights and fans, but nothing else happens. He also tells you that nobody else has done anything with his computer. Nothing has been added or changed, since it worked the day before. You decide to try to re-create the problem, and when you turn on the computer, there are lights and fans, but no beeps and no video. You notice that the keyboard light does not come on.
What can you determine about the problem with Thomas's computer? (Select all that apply.)

A) Motherboard has failed.
B) Video card is not working properly.
C) Processor has gone bad or is not seated properly.
D) Power supply is not working properly.