Is the following Python code valid?

class B(object):
  def first(self):
    print("First method called")
  def second():
    print("Second method called")
ob = B()
B.first(ob)

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

A. Using the class keyword B. Using the define keyword C. Using the classdef keyword D. Using the class method

A. Instances of a class B. Built-in functions C. Special data types D. Global variables

A. Using the class name and parentheses B. Using the create() method C. Using the new keyword D. Using the object() method