单项选择题
Given that the elements of a PriorityQueue are ordered according to natural ordering， and： What is the result？（）
A.apple pear B.banana pear C.apple apple D.apple banana E.banana banana
多项选择题 Which three code fragments， inserted independently at line 6， will compile？（）
多项选择题 Which two， inserted at line 11， will allow the code to compile？（）
单项选择题 What is the result？（）
