Our body conduct and generate electricity. Every cell in our body contain ions - charged elements as sodium, potassium, calcium, and magnesium. They have a specific electrical charge, which is used to generate electricity. Here is a video that explains electrictrical essense of a body: https://m.youtube.com/watch?v=1-NA86aAMvY. And don't forget about water: by itself water is neutral, but it is very effective to dissolve ions, which conduct electricity.
To do it we need a microbit, buzzer, wires and a fruit. The wiring is presented below:
Then, we need to write a code for micro:bit to make it play sound. I used the platform vittascience (https://en.vittascience.com/microbit/) to generate a code for this project:
The code include three different variations depending on the pin to which you connect the buzzer. Connection with pin P0 lead to the general music from Star Wars, connection with pin P1 will play a gamma, connection with P2 will lead to the sounds of R2D2 robot from Star Wars.
That's how it works: