The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task， SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index？（）

A、An update in a leaf row takes place.

B、The index becomes invalid after the update.

C、The leaf block containing the row to be updated is marked as invalid.

D、A row in the leaf block of the index for the key value is deleted and inserted.