Which operation converts a string to all lowercase letters?

Which operation converts a string to all lowercase letters?

• A. Lower
• B. Upper
• C. Substring
• D. Arithmetic operators

Answer: (A)

This question tests changing the case of letters in a string. The operation that converts all characters to lowercase applies a function that maps each letter to its lowercase form, so a string like 'AbC' becomes 'abc'. This is useful for normalizing text so comparisons ignore case or for consistent display. The other options don’t fit: converting to uppercase would produce 'ABC'; extracting a substring would take only a portion of the string; and arithmetic operators deal with numbers, not text casing.

This question tests changing the case of letters in a string. The operation that converts all characters to lowercase applies a function that maps each letter to its lowercase form, so a string like 'AbC' becomes 'abc'. This is useful for normalizing text so comparisons ignore case or for consistent display. The other options don’t fit: converting to uppercase would produce 'ABC'; extracting a substring would take only a portion of the string; and arithmetic operators deal with numbers, not text casing.