单项选择题

Questions 169-171 refer to the following manual.

TROUBLESHOOTING

If your TV does not work,check the following points:

PICTURE SOUHD POSSIBLE CAUSES WHAT TO DO
No picture Noise Not properly tuned Adjust tuning
Picture visible No sound

·Volume control dialturned too low

·Earphones inserted

·Turn up volume

·Disconnectearphones

Picture all white Sound heard Brightness control not set correctly Adjust brightness control
Picture dark or blurred Sound heard Brightness control not set correctly Adjust brightness control
What does the manual advise if the picture is all white

A. Turn down the volume
B. Adjust the brightness control
C. Adjust the tuning
D. Disconnect the earphones