The Following Four Junior High School Science Teachers Are Teaching

The following four junior high school science teachers are teaching the concept molecule to their students. In each classroom, some of the students are frequently using formal operational reasoning, whereas others are consistently using concrete operational reasoning. In which classroom are the concrete operational thinkers most likely to have difficulty understanding?

A) Mr. Armani lets students touch and manipulate concrete models of various molecules.
B) Mr. Bendetti lets students look at the same concrete models that Mr. Armani has used.
C) Mr. Carmen verbally describes how different elements are made up of different numbers of neutrons, protons, and electrons.
D) Mr. Davidson has students role-play being neutrons, protons, and electrons. The "neutron" and "proton" students huddle together in the middle of the room, and the "electrons" move around them.