Select the most appropriate meaning of the given idiom. Walls have ears

for everyone A blunt lie To listen by someone in disguise A foolish and useless search

To listen by someone in disguise

The most appropriate meaning of the idiom "walls have ears" is be careful what you say, someone might be listening. The other options are not correct meanings of the idiom "walls have ears". For everyone means that something is available to everyone. A blunt lie is a lie that is told directly and without hesitation. To listen by someone in disguise means to listen to someone without them knowing. A foolish and useless search is a search that is unlikely to be successful.