Which of these is a private data field?

def Demo:
def __init__(self):
    __a = 1
    self.__b = 1
    self.__c__ = 1
    __d__= 1

A. To model real-world entities and their interactions B. To maximize efficiency C. To use fewer lines of code D. To create simple programs

A. A specific data type B. A built-in function C. An instance of a class D. A variable in Python

A. A blueprint for creating objects B. A built-in function C. A variable in Python D. A specific data type

A. Polymorphism B. Abstraction C. Inheritance D. Encapsulation