Sarah started with $150 of credit card debt. Each month, she paid $50 of her bill, but by the next month the interest made her remaining bill double. What is the recursive formula for Sarah’s credit card bill?
A. Dn+1=50Dn-2
B. Dn=1=2Dn
C. Dn+1=2Dn-50
D. Dn+1=2Dn+50