Which Statement Is TRUE Regarding the Sense of Smell

Multiple Choice

Which statement is TRUE regarding the sense of smell?

A) Humans have the ability to detect a maximum of about 500 different scents.
B) Humans can identify by name a maximum of about 300 different scents.
C) We smell something when odor molecules in the air get inhaled into the nose.
D) We smell something when chemicals in the air interact with chemicals given off by the nose.