Step 1: Understanding the question.
This question asks about the type of data structure that Python uses to represent a sequence of characters. In Python, strings are used to represent sequences of characters, and they are encoded using Unicode.
Step 2: Analyzing the options.
(A) alphabets: This is incorrect. A string in Python can contain more than just alphabets, such as numbers and symbols.
(B) ASCII: This is incorrect. Although Python supports ASCII encoding, it uses Unicode by default, which encompasses more characters.
(C) Unicode: Correct — Python uses Unicode to represent strings, which allows it to handle a wide range of characters from different languages and symbols.
(D) None of these: This is incorrect. Unicode is the correct answer.
Step 3: Conclusion.
The correct answer is (C) Unicode, as Python uses Unicode to represent sequences of characters in strings.