下面是一道
Read the following SAT test question, then click on a button to select your answer.
A 25-foot ladder is placed against a vertical wall of a building, with the bottom of the ladder standing on concrete 7 feet from the base of the building. If the top of the ladder slips down 4 feet, then the bottom of the ladder will slide out
A.4 feet
B.5 feet
C.6 feet
D.7 feet
E.8 feet