Miffy,who Is 20 Years Old,is Thrilled to Report That She

Miffy,who is 20 years old,is thrilled to report that she just took Alfred Binet's test and her mental age is 15.What should Miffy be told about her score?

A) she has a really good score; few people score 15 points above their age.
B) she has an average score; most individuals above the age of 15 score a mental age of 15.
C) she has a terrible score; she scored the same as the average 15-year old.
D) She has a terrible score; most 15-year olds score better than 15.