Bob is considering selling some of his receivables. Which of the following must occur for control over the receivables to be surrendered?

a. All of these must occur

b. Each transferee has the right to pledge or exchange the asset it received

c. The transferred assets have been isolated from the translator

d. the transferor does not maintain effective control over the transferred assets through either repurchase or redemption agreements before maturity or the ability to cause the transferee to return the assets