Answer:
Marshall will develop a mature style of reasoning about morality
Explanation:
In the authoritative style of parenting the parents set down rules and expect the child to understand why the rules have been set up, the way they have. The parents expect the children to understand the consequences of their actions. The curiousity of the child is nurtured.
Here, Marshall is trying to understand what is moral and amoral. The authoritative style allows children to question their parents. Marshall would question about morality and reach the best conclusion as all his questions would be answered.
Hence, Marshall would develop a mature style of reasoning about morality