[Portraits] Tori, a Famous Portrait Painter, Agreed to Paint Harry's

[Portraits] Tori, a famous portrait painter, agreed to paint Harry's portrait for $4,000. She also agreed to paint the portraits of Gabby's two Corgi dogs, Queenie and Prince. Gabby agreed to pay Tori $10,000 for the two Corgi portraits. Tori charged Gabby more because she met the spoiled dogs, and they really got on her nerves. Tori subsequently fell behind on finishing Harry's portrait, so she assigned the right to receive the money for the dog portraits to her assistant, Justin, and delegated the duty to Justin to paint the dog portraits. Justin eagerly accepted, and painted the portraits. Tori also assigned to Justin the right to receive payment from Harry to satisfy various payments she owed him for other duties. The contract Tori had with Gabby did not address assignment in any way. The contract Tori had with Harry, however, prohibited the right to assign payment for services received. Harry considered himself to be an experienced business person and insisted on that antiassignment clause because he had read somewhere that such a provision was a good idea. Tori finished the portrait of Harry and called him to come and pick it up. Meanwhile, a disgruntled secretary who disliked Tori told both Gabby and Harry about the assignments to Justin. Gabby was furious and refused to pick up the portrait or to pay anyone. Harry likewise refused to pay for his portrait.
-What would be the most likely result if Justin sues Gabby for the $10,000 payment?

A) Justin will win only if Justin did a good job on the portraits.
B) Justin will lose because Gabby's only obligation is to pay Tori.
C) Justin will win unless Gabby can prove that Justin knew that she did not want him to do the portraits.
D) Justin will lose unless Justin can prove that he was unaware that Gabby did not want him to do the portraits.
E) Gabby will win because the portrait was personal in nature and could not be delegated.