What do the words active production suggest in Paragraph 4 of this passage?

A research team from Northwestern University observed that to achieve the positive brain development from musical training, music students had to be active participants. There were differences found between the kids who attended a more passive music appreciation class, and the ones who learned to play instruments. It was the active production of music that rewired the brain. Using electrodes on the students’ heads, scientists were able to see how actively the brain responded when students generated music.

Responses

Producing music shows activity in the brain.

Listening to music helps students appreciate class.

Playing an instrument is beneficial to brain development.

Students respond better to music when they play it themselves.