The table below shows typical intelligence quotient $($IQ$)$ results from studies of family members of those with intellectual disability $($ID$).$ Which group's ID is most likely caused by genetic risk factors shared with family members?

Group

Probands

IQ range of sibs

Mean IQ of sibs

A

Severe$/$moderately disabled

$85125$

$100$

B

Mildly disabled

$55125$

$85$

Group of answer choices

B

A