Moore Money Inc

Moore Money Inc. has a profit margin of 11% and a retention ratio of 70%. Last year, the firm had sales of $500 and total assets of $1,000. The desired total debt ratio is 75%. What is the firm's
Sustainable growth rate?

A) 2.5%
B) 4.0%
C) 7.1%
D) 11.3%
E) 18.2%