The heat moves from the hot chocolate to the handle of the spoon by a process called thermal conduction.
It is the transfer of heat energy from one object to another when they are in contact with eachother.
Hope this answers your question.
Answer:
As the tines of the tuning fork vibrate at their own natural frequency, they created sound waves that impinge upon the opening of the resonance tube. These impinging sound waves produced by the tuning fork force air inside of the resonance tube to vibrate at the same frequency.