Which of the following is TRUE of children's effective problem-solving?
A. Most students today are given ample opportunities to practice strategic problem-solving.
B. The best strategy for solving a particular problem is normally discovered by children themselves while exploring the world independently.
C. Children benefit least when using multiple strategies in problem-solving.
D. Children benefit most when using more than one strategy in problem-solving, even if some didn't work or didn't work well.