Why is this A?

Please use the following information to answer question 41. BetaShoe manufactures shoes in two divisions, the Sole Division, and the Assembly Division. The Sole Division manufactures soles and transfers them to the Assembly Division, which completes the shoes and sells them to retailers. The market price for the Assembly division to purchase a pair of soles is $20. The Sole Division currently has sufficient capacity to manufacture all the soles the Assembly Division requires. What is the overall corporate income for Scenario A and Scenario B if the Assembly division sells 100,000 pairs of shoes for $60 per pair? a. No difference in net income under scenario A and B b. $ 100,000 more net income under scenario B c. $ 100,000 more net income under scenario A d. $500,000 more net income under scenario B e. $500,000 more net income under scenario A