Of the following activities, which best introduces to students the process skill of classification?
A. Measuring the time it takes a marble to reach the bottom of an inclined plane when dropped from different heights
B. Sorting a collection of objects into metals and nonmetals, then sorting the metals into magnetic and nonmagnetic
C. Modeling the faces of the moon using a foam ball and light, then describing and drawing their observations
D. Representing the stages of the life cycle of a butterfly using craft materials provided by the teacher
