Institution: SONALI BANK LTD Exam: Sonali Bank Ltd - Assistant Programmer - 26.08.2016 ||
Topic: ICT (তথ্য ও যোগাযোগ প্রযুক্তি), Subject: Computer and ICT (তথ্য ও যোগাযোগ প্রযুক্তি)

Best Answer Explained in Below-:

The practice of using setter and getter methods in programming is primarily known as **encapsulation**. Encapsulation is a fundamental principle of object-oriented programming (OOP) that promotes the bundling of data (attributes) and methods (functions) that operate on the data into a single unit or class.

By utilizing setter and getter methods, a class can control access to its attributes. The setter method allows modification of a variable while enforcing rules or validations before the actual change occurs. Conversely, the getter method provides a way to retrieve variables while maintaining control over how the data is accessed. This mechanism protects the internal state of an object from unintended interference and misuse, ensuring that only validated or necessary data is exposed to the outside world.

This controlled access enhances data integrity and fosters a clean and maintainable code structure, separating the internal representation of the object from how it is perceived or interacted with from outside. Other options like polymorphism, inheritance, and recursion represent different OOP concepts but do not encapsulate this specific functionality of protecting and managing data access. Thus, the correct answer is A) encapsulation.