What is the function of the UPDATE statement in SQL?

The UPDATE statement in SQL is specifically designed to modify existing data within a record in a database table. When you use the UPDATE statement, you specify which table you want to update and then define the changes that need to be made for particular records based on certain conditions. This means you can change one or more fields in a record to reflect new information, such as updating a user's email address or changing the price of a product.

For instance, if you have a table of customer information and you want to change the address for a specific customer, you would use the UPDATE statement to locate that customer’s record and modify the address field without altering any other information in that record.

It's important to ensure that the WHERE clause is correctly specified in the UPDATE statement to avoid unintentional modification of records. If the WHERE clause is omitted, all records in the table would be updated with the same new value, which can lead to data inconsistencies.

Thus, the correct answer reflects the primary purpose of the UPDATE statement in SQL, which is to modify existing data in a record.