Which are two triggers in SQL?

• A. After create and before drop.
• B. Before update and after select.
• C. Before delete and after truncate.
• D. Before insert and after insert.

Answer: (D)

Triggers automatically run in response to certain data-change events on a table, and they can fire either before the operation or after it completes. The sequence “before insert” and “after insert” shows two valid triggers tied to the same kind of operation (inserting rows) but with different timing. A before-insert trigger can inspect or modify the data as it’s about to be inserted, ensuring validity or adjusting values. An after-insert trigger runs once the row exists, which is useful for actions that depend on the new data being present—like logging the insertion or updating related tables.

The other options mix events that aren’t standard for typical row-level triggers: selecting doesn’t trigger DML events, and create, drop, or truncate are DDL operations that are handled differently in most database systems (often via DDL triggers or not at all in simple trigger scenarios). So the combination of before insert and after insert best reflects valid, commonly supported trigger timings for a single data-change event.