A girl currently runs 3 miles in 45 minutes. Her long-term goal is to run 3 miles in 30 minutes within one month.
What would be an appropriate short-term goal for her first week of training?
A. to run 3 miles in less than 12 minutes
B. to run 3 miles in less than 15 minutes
C. to run 3 miles in less than 20 minutes
D. to run 3 miles in less than 40 minutes