That statement is true
This result can be used as proof that certain type of genotype among humans are not affected by environmental factors. (some of us are born to be physically stronger or intellectually inferior without making any effort, environmental factors could only resulted in very little deviation.)
B
to convince is to persuad someone to think in your point of view
It is important to talk to them young so they are better able to mature as they get older. For example, teaching boys it’s ok to show emotions and such which can help then thrive more. This also applies to girls, with saying that they don’t have to be moms or get married and so on. The parents should go on about it by talking to them little by little like asking them what they think about the topic and what they would do.