Either lower or uppercase

What this Python string-method question tests

This is an easy practice question designed to verify your fluency with Python's built-in string methods and their return values. It rewards careful reading of how these methods behave and what they actually return—skills that matter in both interviews and production code.

To approach this kind of problem, trace through the method calls step by step, paying close attention to what each method does to the input and what it returns. Even simple-sounding string operations have precise, documented behaviour that differs in subtle but important ways. Getting comfortable with Python's string API through direct observation builds the foundation for writing correct code quickly.

• String method return types and their effects
• Method chaining and order of operations
• Distinguishing between in-place modification and immutable string operations