Answer:
C. To create a funny, marketable item
Step-by-step explanation:
Gary Dahl was an entrepreneur who created the 'Pet Rock',
He found his business inspiration from hearing his friend's complaint about the hardship that pet owners always have to face. Such as cleaning up the pets' feces, bathing them, feeding them ,etc.
He used this as an idea to make a funny collectible toys called the Pet Rock. He included a manual that the buyers can use in order to treat these rocks as an actual pet.