Which Term Describes Each of the Following Concrete Operational Skills

Multiple Choice

Which term describes each of the following concrete operational skills? (1) understanding that an increase in one dimension of a substance can make up for a loss in another dimension of the substance; (2) understanding that changing the shape of a substance doesn't change its amount; (3) realizing that candy is the name for both chocolate and gummy bears.

A) (1) decentering; (2) conservation of mass; (3) class inclusion
B) (1) conservation of mass; (2) class inclusion; (3) decentering
C) (1) decentering; (2) class inclusion; (3) conservation of mass
D) (1) conservation of mass; (2) decentering; (3) class inclusion