Answer:
the second one
Explanation:
I'm just good at social studies -_-
<span>The answer is "Reality principle".
In Freudian psychology and analysis, the reality principle refers to the capacity of the psyche to survey the truth of the outside world, and to follow up on it accordingly, instead of following up on the pleasure rule.
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The correct answer is methylation.
This process refers to the addition of methyl groups to the DNA molecule, when the activity of such DNA segments is slightly altered. The more we age, the less methylation there is, which is why the genes of the elderly are different from those of young people.