PLEASE HELP What form or rule is demonstrated in this sentence?

The plan was this: divide the troops, surround the enemy, and capture the headquarters.

colon used to divide two clauses
commas between adjectives preceding a noun
colon used before a list of items

Colon used before a list of terms.

Explanation:

It goes on to list the steps in the plan.

i think the literacy device is "it's frozen head"

the central idea is basically saying that juveniles that have committed a crime will not have the same consequences as the   adults that have. they will have a softer punishment than what the adults have that is harsh in some ways.