He who pays the piper calls the tune

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Meaning: The person who pays a musician can decide what music he wants to hear. And the person who pays for any service has the right to say exactly what he wants.

Note: piper (noun) = a person who plays the pipe (a musical instrument) | tune (noun) = a melody; a piece of music

Quick Quiz:

Mark tapped his wallet and said to his friends, "He who pays the piper calls the tune", meaning that

he wondered if they'd like to go to a concert he would decide where they would eat he'd spent all his money Source: englishclub.com

Click for answerb.