单项选择题
What is the result？（）
A.2-1 B.2-4 C.2-5 D.3-1 E.3-4 F.3-5 G.Compilation fails. H.An exception is thrown at runtime.
What is the result？（） A.Compilation fails.B.An exceptio...
A.Compilation fails. B.An exception is thrown at runtime. C.The variable first is set to null. D.The variable first is set to elements[0].
What is the result？（） A.1B.2C.12D.Compilation fails.E.N...
A.1 B.2 C.12 D.Compilation fails. E.No output is produced. F.An exception is thrown at runtime.
What is the result？（） A.2B.24C.234D.246E.2346F.Compilat...
A.2 B.24 C.234 D.246 E.2346 F.Compilation fails.
