Question $2$

The other area is the $\_\_\_\_\_\_\_\_\_\_\_\_\_$ of inheritance itself. Inheritance is a useful mechanism for $\_\_\_\_\_\_\_\_\_\_\_\_$ code; the decision by the designer to $\_\_\_\_\_\_\_\_$inheritance for this purpose should be private and easily changed.

A$.$

visibility $/$ type$/$ code

B$.$

Language $/$ reusing $/$ system

C$.$

visibility $/$ reusing $/$ use

D$.$

Code$/$ use $/$ reusing