Given:

Which statement is true?

A. Both p and s are accessible by obj.
B. Only s is accessible by obj.
C. Both r and s are accessible by obj.
D. p, r, and s are accessible by obj.

題解

在不同套件的繼承關係下,只有public和protected的可見度可以將變數繼承至底下的類別。因此在這題中,只有s變數和r變數可以用Test類別所實體化出來的Test物件存取。但是,obj變數是Acc型態,不是Test型態,因此沒有辦法存取到使用protected修飾的r變數。