For each scenario listed, identify which locking scheme should be applied:

a. Modification is to be made to a table, such as Create, Alter or Dropping the table.

b. An order from a particular client involves a number of line items. The database administrator wishes to verify a particular line item in the order manually before processing the order.

c. A human error caused a faulty entry for salary rise applicable to all employees in a firm’s database. So the database administrator needs to rollback the entire database to undo the incorrect data updates.

d. An account number is to be deleted from a database.