In object-oriented (51) , objects can be viewed as reusable components, and once the programmer has developed a (52) of these components, he can (53) the amount of new coding required. But (52) a (54) is no simple task because the integrity of the Original software design is critical. Reusability can be a mixed blessing for user, too, as a programmer has to be able to find the object he needs. But if (55) is your aim, reusability is worth the risk.

（52）是（）