easy

What calls for help, when written in capital letters, is the same forwards, backwards and upside down?
Common Wrong Answers
“WOW”
While 'WOW' is a palindrome and looks the same forwards and backwards, it does not represent a call for help, and it does not appear the same upside down.
“MOM”
'MOM' is also a palindrome, but it does not convey a call for help like 'SOS' does, and it doesn't look the same upside down.
“DAD”
'DAD' is another palindrome, but like the others, it lacks the meaning of a distress signal and does not maintain its form when turned upside down.
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