Have you ever remembered something with your nose? Maybe the smell of hot dogs makes you think of being at a baseball game. Or the smell of barbequed meat reminds you of a night around a fire. Scientists know that smells can make people think of powerful memories. Wouldn't it be great to somehow save those memories?      _ is exactly what Mark Crames, a businessman making perfumes  , is trying to do. His company, Demeter Fragrance, makes more than 200 kinds of perfumes. "Imagine every smell in the world as a musical note," Crames said. "We try to join those notes to make a piece of beautiful music." He has made many perfumes and he got the idea from plays, storms and even animals.     Everyday smells mean different things to different people. "A perfume called Poison Ivy might make you think of sadness or surprise," Crames says. "But it could make another person think of a great time at summer camp."     Crames produces perfumes using a high-tech method called headspace technology. This month, Crames is making scent for Tootsie Roll and Junior Mints. Not every smell can be easily copied. "One of our most needed perfumes is a little dog's breath," he says. "But it is so chemically complicated   that it's very hard to get."     What scent would you like to bottle? A zoo? Or grandma's old house? Crames may be able to help you bring back your memories, so all you have to do is have a smell when you want to remember. The passage mainly tells us   _  .
how to remember things how to make perfumes a businessman with good smell smells can help us remember
Question: Have you ever remembered something with your nose? Maybe the smell of hot dogs makes you think of being at a baseball game. Or the smell of barbequed meat reminds you of a night around a fire. Scientists know that smells can make people think of powerful memories. Wouldn't it be great to somehow save those memories?      _ is exactly what Mark Crames, a businessman making perfumes  , is trying to do. His company, Demeter Fragrance, makes more than 200 kinds of perfumes. "Imagine every smell in the world as a musical note," Crames said. "We try to join those notes to make a piece of beautiful music." He has made many perfumes and he got the idea from plays, storms and even animals.     Everyday smells mean different things to different people. "A perfume called Poison Ivy might make you think of sadness or surprise," Crames says. "But it could make another person think of a great time at summer camp."     Crames produces perfumes using a high-tech method called headspace technology. This month, Crames is making scent for Tootsie Roll and Junior Mints. Not every smell can be easily copied. "One of our most needed perfumes is a little dog's breath," he says. "But it is so chemically complicated   that it's very hard to get."     What scent would you like to bottle? A zoo? Or grandma's old house? Crames may be able to help you bring back your memories, so all you have to do is have a smell when you want to remember. The passage mainly tells us   _  .
A. how to remember things
B. how to make perfumes
C. a businessman with good smell
D. smells can help us remember
Answer: