Which of the following statements about strings is correct?

• A. Strings can only be numeric
• B. Strings can contain variables
• C. Strings are immutable
• D. Strings cannot be concatenated

Answer: (C)

Strings are immutable in Python, meaning once a string is created, it cannot be modified. This immutability implies that any operation that seems to change a string actually creates a new string. For example, if you try to change a single character in a string or append to it, Python will create a new string rather than modifying the original.

Understanding immutability is crucial because it affects how you manipulate strings in your programs. Since strings cannot be altered directly, functions that appear to change them, like slicing or concatenation, will result in new string objects. This concept is foundational in Python programming and impacts how strings are stored and how memory is used, leading to efficient and predictable handling of text data.

The other options describe characteristics that are not true for strings in Python. Strings can include alphabetical characters, symbols, and numeric data; they can contain variables when formatted appropriately; and strings support concatenation, allowing them to be combined using operators or functions.