Answer :
Camilia played a lovely little song ans then proudly showed off her new ocarina, which some people call a sweet potato.
The correct sentence is: 'Camilla played a lovely little song and then proudly showed off her new ocarina, which some people call a sweet potato.'
Camilla played a lovely little song on her new ocarina and then showcased it. The sentence construction requires proper punctuation to clarify that the phrase 'which some people call a sweet potato' is a non-restrictive clause giving additional information about the ocarina. Therefore, a comma is needed before 'which' to integrate this additional information smoothly into the sentence. This makes the message clear and avoids any possible confusion. Without the comma, it could seem as though Camilla showed off an ocarina and a sweet potato as separate items, which is not the intention of the sentence.