Which of These Is an Invalid Use of the Deviation

Which of these is an invalid use of the deviation IQ to measure intelligence differences?

A) to screen for scholastic aptitude for college seniors applying to medical school
B) to assess general cognitive functioning for young adults in the military
C) to study intelligence differences between thirty-year-olds who are either self-made millionaires or bankruptcy filers
D) to study intelligence differences between young adults and senior citizens