Answer: ঘ)
Encapsulation
Explanation:
Encapsulation in Object-Oriented Programming (OOP):
Definition: Wrapping data (attributes) and methods
(functions) that operate on the data into a single unit (class)
and restricting access to some of the object’s components.
Purpose: Protects object integrity by preventing unauthorized
access or modification.
Example:
class BankAccount {
private:
double balance; // cannot be accessed directly outside
the class
public:
void deposit(double amount) { balance += amount; }
double getBalance() { return balance; }
};
balance is hidden (private) → can only be accessed via
methods → encapsulation.
Other options are incorrect:
ক) Inheritance→→Allows
a class to derive properties from another class
খ)
Polymorphism→→Allows one interface, multiple forms
গ) Abstraction→→Hides
implementation details but focuses on what an object does, not access control