Increasing Ability in Systematic Planning Ability Accounts for Which of the Following

Increasing ability in systematic planning ability accounts for which of the following findings?

A) In a memory task, young children searched all the other boxes rather than the boxes that had a cue for the category they were asked to remember.
B) When Navajo children were asked to solve a maze task, they performed more slowly than Euro-American children but made fewer errors.
C) When Liberian children who had never been to school were asked to recall items that were grouped in a meaningful way, they performed at a level comparable to children in the United States.
D) In situations where children are not actively engaged in a challenging problem-solving task, they are less likely to be able to explain what they are thinking about.