Six-year old Billy and his 20-year-old brother Sam both obtain valid IQ scores of 110. Their mother comments that Billy is really smarter since his score is particularly impressive ?for a 6-year-old.? Which of the following would likely be correct?
a. Billy is not currently smarter, but he will be when he and Sam are both adults.
b. IQ is age adjusted, so Billy and Sam are at the same percentile, relative to their respective age groups.
c. Billy and Sam would be about equally matched on games requiring intelligence, such as chess.
d. Their mother is correct.