Amy bought and then sold 15 n avocados, for some positive integer n. She made a profit of \$ 100. (Her profit is the difference between the total amount that she earned by selling the avocados and the total amount that she spent in buying the avocados.) She paid \$ 2 for every 3 avocados. She sold every 5 avocados for \$ 4. What is the value of n ?
Answer Choices
A. 100
B. 20
C. 50
D. 30
E. 8