A developer needs to confirm that a Contact trigger works correctly without changing the organization's data. What should the developer do to test…

Apex test methods are the standard mechanism for verifying the functionality of triggers and classes. A critical feature of the Apex testing framework is that any database changes (DML operations) made during a test run are not committed to the organization's database. The transaction is automatically rolled back upon completion. This allows the developer to simulate record creation, updates, and deletions to fire the trigger and assert its behavior without altering any persistent organizational data, directly fulfilling the requirements of the scenario. The Developer Console provides a user interface to run these test classes.

1. Salesforce Apex Developer Guide

"Testing Apex" Chapter

"Isolation of Test Data from Organization Data" Section: "By default

Apex tests don’t commit any data to the database... Test data is rolled back at the completion of test execution. This rollback behavior is handy for testing because you don’t have to clean up your test data after the test run."

2. Salesforce Apex Developer Guide

"Developer Console" Chapter

"Running Tests in the Developer Console" Section: This section details the procedure for using the Test menu to run test classes. "To run tests from the Developer Console

click Test and select an option."

3. Trailhead

"Apex Testing" Module

"Get Started with Apex Unit Tests" Unit: "To prevent fake data from being saved to your org

test methods don’t commit any data. The platform runs test methods in a special context that provides this safeguard."