Which function converts all characters in a text string to lowercase?

• A. UPPER
• B. TRIM
• C. LOWER
• D. PROPER

Answer: (C)

Converting all characters in a text string to lowercase is about standardizing text for comparisons or consistent display. The function that does this is LOWER. It takes a text input and returns a version where every letter is in lowercase, regardless of how it was originally typed. For example, LOWER('Hello World') yields 'hello world'. This is especially useful for case-insensitive comparisons or searches, since you can convert both sides to the same case before comparing. The other options perform different tasks: UPPER turns all letters into uppercase, TRIM removes extra spaces at the ends, and PROPER capitalizes the first letter of each word. So LOWER is the right choice for converting to lowercase.