Why do scientists use identical twins to study genetics?

because they share the exact same genome, scientists attribute these differences to the environment. ... The basic idea behind studying identical twins is that the results can better determine whether a certain trait, illness, or disorder is influenced more heavily by genetics or by the environment

Explanation:

hope it helps :p

Twins are the closest DNA wise

Explanation:

Twins have very similar DNA from looking the same most of the time so scientists can see why they look so similar or why they can seem like the same person, giving scientists more answers on how DNA actually works.

i believe it's c. the trait for large beaks will be passed on to future generations through natural selection.

since eventually smaller beaks would have to find another source of food or even eventually just die out from the lack of food.