What is the primary function of the LOWER function in Excel?

The primary function of the LOWER function in Excel is to convert text to lowercase. This function is particularly useful when you need to standardize text data and ensure that all letters are in lowercase, which can be important for data consistency, especially in cases involving comparisons or sorting. For instance, when merging data from multiple sources, using the LOWER function can help eliminate discrepancies caused by variations in capitalization.

While other functions in Excel accomplish different tasks, such as capitalizing the first letter of each word or converting text to uppercase, the LOWER function specifically targets the transformation of all characters in a string to their lowercase equivalents. This precision in functionality is what distinguishes the LOWER function from the other options provided.