What does the idiom 'barking up the wrong tree' mean?

[Barky]

English Language Tests, Intermediate level

ESL/EFL Test #279 "English Slang Idioms (1)", question 4

"That is nowhere near the answer. You're ......... up the wrong tree."

(a) cutting
(b) barking
(c) digging
(d) painting

English Language Tests, Intermediate level

ESL/EFL Test #279 "English Slang Idioms (1)", answer 4

"That is nowhere near the answer. You're barking up the wrong tree."

Correct answer: (b) barking

Your answer was: incorrect
"That is nowhere near the answer. You're cutting up the wrong tree."
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I can't understand this idiom barking up the wrong tree. Can someone help me?
Thanks
Barky

[Alan]

Hi,

If you tell someone that they are barking up the wrong tree, it means they have misunderstood the situation or they are following the wrong clue or suggestion.

Alan
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English as a Second Language
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