To remove unnecessary semicolons from a string field named Name, you should use the REPLACE function. The REPLACE function allows you to substitute all occurrences of a specified substring (in this case, semicolons) with another substring (an empty string in this case). The other functions, such as TRIM, SPLIT, and CONTAINS, are not suitable for this specific task because they serve different purposes: TRIM removes whitespace from the beginning and end of strings, SPLIT divides a string into parts based on a delimiter, and CONTAINS checks for the presence of a substring within a string.