Which of the following is MOST likely causing an intermittent flashing LED on an IR receiver when the remote control is not being used?

Which of the following is MOST likely causing an intermittent flashing LED on an IR receiver when the remote control is not being used?

A.
The power supply is faulty and should be replaced.

B.
The heat from a heating, ventilation, and air conditioning (HVAC) register is being received as infrared noise.

C.
The radio frequency interference (RFI) is being received as noise.

D.
A plasma display is emitting infrared noise.