an example of consideration

Question 5

  1.  Which of the following is an example of consideration?
    A benefit to the promisor but not a detriment to the promisee
    A detriment to the promisee but not a benefit to the promisor
    A promise to do something, a benefit to the promisor, or a detriment to the promisee
    An accepted offer
    A valid counteroffer