The CHECK constraint is generally used to limit the range of values that can be placed in a column. If a CHECK constraint exists on the department_id to only allow values such as 80 (assuming from the context provided):
A . UPDATE emp80 SET department_id=90 WHERE department_id=80: This UPDATE statement attempts to set the department_id to 90 for rows where it is currently 80. If there is a CHECK constraint preventing department_id from being anything other than 80, this statement would violate that constraint.
Incorrect options:
B: DELETE operations do not affect CHECK constraints as they do not involve modifying or setting column values.
C and D: SELECT statements do not modify data and thus cannot violate data integrity constraints like CHECK constraints.