A particular allele variant of SLC6A4 is believed to make children especially reactive to their rearing environment. For children with this allele variant, high maternal responsiveness is associated with of conscience at 15 to 52 months of age. Conversely, for children with this same variant, low maternal responsiveness is associated with of conscience.

Answer is high levels; low levels

Refer below.

Explanation:

A particular allele variant of SLC6A4 is believed to make children especially reactive to their rearing environment. For children with this allele variant, high maternal responsiveness is associated with high levels of conscience at 15 to 52 months of age. Conversely, for children with this same variant, low maternal responsiveness is associated with low levels of conscience.

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.