A class can not be called "tightly encapsulated" unless which of the following are true? a. The data members can not be directly manipulated by external code. b. The class is declared final. c. It has no public mutator methods. d. The superclass is tightly encapsulated.
The answer is given: a,d Description to "d", if the super class is not tightly encapsulated no subclasses can be tightly encapsulated. Please clarify.