The str.split() method returns a list of substrings from the original string, using the provided argument as the delimiter. In this case, x.split(",") splits the string "Hello, World!" at the comma ,. The delimiter itself is removed, but any surrounding characters, including the space after the comma, are preserved in the resulting substrings. Therefore, the method produces a list containing two elements: the string "Hello" and the string " World!", which includes the leading space.

A. ["Hello", "World!"]

This is incorrect because the split() method does not automatically remove whitespace adjacent to the delimiter. The space after the comma is part of the second substring.

C. ["Hello, World!"]

This is incorrect. This output would occur if the delimiter (,) was not found in the string, but it is present, causing the string to be split.

D. "Hello, World!"

This is incorrect because the split() method returns a list object, not a str (string). The print() function would display the list's representation.

1. Python Software Foundation. (2023). Built-in Types — Python 3.12.0 documentation.

Section: Text Sequence Type — str, str.split(sep=None, maxsplit=-1)

Details: The official documentation states, "Return a list of the words in the string, using sep as the delimiter string." It does not mention any automatic trimming of whitespace from the resulting elements when a separator is specified, confirming that characters like the space in " World!" are preserved.

2. Guttag, J. V. (2016). Introduction to Computation and Programming Using Python, Second Edition. MIT Press.

Chapter/Section: 4.1.1, Strings, Tuples, and Ranges (related to string methods).

Details: University textbooks used in courses like MIT's 6.0001 explain that string methods operate precisely. The split method divides a string based on the delimiter, and any characters not part of the delimiter become part of the resulting list elements. For example, 'a, b'.split(',') results in ['a', ' b'].

3. Severance, C. R. (2016). Python for Everybody: Exploring Data Using Python 3.

Chapter: 6, Strings.

Section: 6.4, String Methods.

Details: This widely used university textbook explains that the split method breaks a string into parts and produces a list of strings. The examples provided illustrate that the delimiter is consumed, but adjacent characters are not, which aligns with the behavior seen in the question.