Humans can smell as many as 10,000 different odors but have significantly fewer types of olfactory receptors. which of the following is the best explanation for why humans can distinguish so many smells?

a. the sensation of a single, distinct smell is a combination of a variety of chemicals that stimulate different combinations of olfactory receptor cells all at once.
b. taste receptors that are active at the same time influence the subtlety of what we smell.
c. the belief that we can smell so many different distinct odors is a psychological process referred to as an uncinate fit or olfactory hallucination.
d. the olfactory pathway travels to a location in the brain in which memories are formed and we simply mix this new sensory information with old memories.