Geneticist: "Adopted Children Often Display Different Characteristics from Their Siblings

Multiple Choice

Geneticist: "Adopted children often display different characteristics from their siblings, choosing different careers, values, or hobbies. Clearly some of our preferences are therefore biologically innate, and are not influenced by the environments in which we are raised."
Which of the following, if true, would most weaken the geneticist's argument?

A) Biological children also display very different attitudes in regard to career, values, and hobbies.
B) Scientists are unable to link any genes to certain propensities.
C) Many people change their preferences as their life progresses.
D) Children who are raised together but are far apart in age are also likely to have very different opinions.
E) Children often try to mimic the preferences of their parents, but then rebel in adolescence.