Bridget teaches a dog training class at her local animal shelter. She wants to provide the dog owners with some philosophical inspiration. According to Aristotle's metaphysics and ontology, what is true about the essence of a dog?
a) A dog is a non-human object and therefore has no essence.
b) The essence of dog can only exist in actual dogs and nowhere else.
c) The essence of a dog exists in Platonic Heaven.
d) Each dog has its own unique essence.