单项选择题
A.81
B.82
C.91
D.92
E.Compilation fails.
F.An exception is thrown at runtime.
多项选择题 AteamofprogrammersisreviewingaproposedAPIforanewutilityclass.Aftersomediscussion，theyrealizethattheycanreducethenumberofmethodsintheAPIwithoutlosinganyfunctionality.Iftheyimplementthenewdesign，whichtwoprincipleswilltheybepromoting？（）
单项选择题 WhichManclassproperlyrepresentstherelationship"ManhasabestfriendwhoisaDog"？（）
多项选择题 Which two， independently， will allow Sub to compile？（）
