Which of These Scenarios Represent a Token Economy in Practice

Which of these scenarios represent a token economy in practice?

A) Desirable behavior are reinforced with poker chips or checks on cards,while undesirable behaviors are punished by loss of privileges.
B) Money is taken from the individual and managed as per behavior of that individual.
C) A man experiences a positive mood whenever he smells freshly-cut grass because it reminds him of summers in his childhood.
D) A student turns in a paper and is given a grade.