Answer:
Nature
Step-by-step explanation:
Developmentalists believe that moral development predominantly comes from NATURE due to the fact that children are genetically programmed to defend and protect their parents.
It is natural for children to defend and protect their parents due to the love they have for their parents, they can go to any length to make their parent happy by standing by them when they need them most especially when unforeseen circumstances happens.
Children will always fight for their parent because of the bonds they have for them by making sure that they are unhurt.
Therefore it is natural for children to do so because they are naturally genetically programmed for it.