Raul Is Making Potato Soup

Raul is making potato soup. His roommate tastes it and tells Raul it is great, but Raul thinks it needs more salt. He adds just a little salt, and thinks the soup now tastes perfect. However, his roommate tastes it again and tells Raul that the soup is ruined because it is too salty. Which of the following is most accurate?

A) Raul's roommate has a higher absolute threshold than does Raul.
B) Raul has more taste cells on the back of his tongue than does his roommate.
C) Raul is a nontaster.
D) Raul's roommate can detect a smaller just noticeable difference than Raul can.