The correct option is C The environment, then, is not a stamping machine that pounds us into a shape but a cafeteria of options from which our genes and our histories incline us to choose.
The main idea of this paragraph is that the genes get stronger as we age and propel us to make choices best suited to our natures.
Now let us examine the options to complete the paragraph:
Option A- Although it is true that fraternal twins raised apart have remarkable similarities in most respects, still the intervention of the environment has caused several differences in the way they behave.
This line emphasizes the importance of the environment on behavioural differences of fraternal twins. The main idea of the given paragraph, however, is that genes matter more than the environment in shaping behaviour.
Option B- However, it is still not known whether the more abstract attributes like personality, intelligence and likes and dislikes are gene-coded in our DNA, too.
This line talks about attributes gene-coded in our DNA. This is unrelated to the given paragraph, which talks about how our genes guide the choices we make in response to our environment.
Option C- The environment, then, is not a stamping machine that pounds us into a shape but a cafeteria of options from which our genes and our histories incline us to choose.
This line sums up the main idea of the paragraph well- that the environment we are in is like a cafeteria of options, and our genes direct us to the options we choose from the environment. This is hence the right choice to complete the paragraph.
Option D- But even knowing the totality of genetic predictors, there will be many things about ourselves that no genome scan — and for that matter, no demographic checklist — will ever reveal.
This option talks of ‘genome scans’ and ‘demographic checklists’, which have not been discussed in the paragraph. We can hence rule this option out as the right one to complete the paragraph.
Correct Answer: Choice (C)