Which of the following is an example of a project-approach activity for a preschool class?
• A. All the children who are ready for literacy activities work in a group; those who aren't ready play with the blocks.
• B. At 9:00 in the morning every day, half the children in the class do sorting and counting activities while the other half work on an art project. After 20 minutes, the groups switch.
• C. The children work together painting a large cardboard box that they can use in pretend play to represent anything they want.
• D. A class spends several days on various activities about the plumbing in their building, including a field trip to the basement to see how the water heater works.