What is the output of the following code:
with open('data.txt', 'r') as file:
lines = file.readlines()
print(len(lines))

A. file = open('data.txt', 'r') B. file = open('data.txt', 'read') C. file = open('data.txt', 'read mode') D. file = open('data.txt')

A. It ensures that the file is properly closed after usage B. It creates a new file C. It reads the file contents D. It deletes the file

A. By using the write() method on a file object B. By using the save() function C. By using the put() function D. By using the append() method

A. It reads the entire contents of the file B. It writes data to the file C. It closes the file D. It deletes the file