Which Term Describes Each of the Following Concrete Operational Skills

Which term describes each of the following concrete operational skills? (1) Putting objects in order by their size; (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) seriation; (2) conservation of mass; (3) class inclusion
B) (1) conservation of mass; (2) class inclusion; (3) seriation
C) (1) seriation; (2) class inclusion; (3) conservation of mass
D) (1) conservation of mass; (2) seriation; (3) class inclusion