the correct answer is bamboo and silk
Chinese have been the world sole producer of silk for several centuries, a commodity that often caused a balance of trade deficit between the country and the rest of the world. the secret of silk making was also protected with royal decree for a long time, which makes it a popular material for making music instrument. Bamboo is often preferred for its hollow inside.
The correct answer should be Aztecs.
Aztecs were known for consuming humans and sacrificing them to gods. It was common to them.
