S$-6$: Suppose that a September put option with a strike price of $$100$ costs $$20.$ The underlying stock currently sells for $$110$ per shar Under what circumstances will the buyer of the put option earn a profit at the expiration date? it the underlying stock price at expiration is:

less than $$00$ per share

less than $$90$ per share

greater than $$80$ per share

greater than $$90$ per shave