单项选择题
A.Compilation fails.
B.An exception is thrown at runtime.
C.The code executes normally and prints "sleep".
D.The code executes normally, but nothing is printed.
单项选择题 Given: Which is true?（）
单项选择题 Given: Which statement is true?（）
单项选择题 A team of programmers is reviewing a proposed API for a new utility class. After some discussion,they realize that they can reduce the number of methods in the API without losing any functionality.If they implement the new design, which two OO principles will they be promoting?（）
