​Which of These (IF IT WERE TRUE)would Argue AGAINST Spearman's

Multiple Choice

​Which of these (IF IT WERE TRUE) would argue AGAINST Spearman's concept of the g factor?

A) On average, IQ scores have decreased over the last fifty years.
B) ​People with good language skills tend to be below average at math.
C) ​On average, older adults have higher IQ scores than younger adults.
D) ​Dizygotic twins resemble each other in IQ scores more than monozygotic twins do.