Given:



What is the result?

A.

100
210

B. Compilation fails due to an error in line n1
C. Compilation fails due to an error at line n2
D. Compilation fails due to an error at line n3

題解

line n3實體化DoClass類別的物件實體,但是由於DoClass的建構子並沒有使用public修飾字宣告,因此它只能在同一個套件(package)之內被實體化。若在不同的套件下實體化DoClass物件,會發生編譯錯誤。