Which Excel function would be most useful for merging text from two different cells?

The function that is most useful for merging text from two different cells is CONCATENATE. This Excel function is specifically designed to join multiple text strings into one continuous string. When you use CONCATENATE, you can specify the cells or text values you want to combine, and it will output a single cell containing all of those values together.

For example, if you have the text "Hello" in one cell and "World" in another, using CONCATENATE will allow you to combine them into "HelloWorld", or even insert a space or other characters between them, depending on how you set up the function. This makes it a straightforward and efficient way to consolidate information from different cells into a single text field.

In comparison, the other functions listed have different purposes: IF is used for conditional logic, INDEX retrieves a value from a specified position in a range, and SUMIF is utilized for conditional summation based on specified criteria. These functions do not perform the specific action of merging or concatenating text from multiple cells, which is uniquely suited to the CONCATENATE function.