A roll-up summary field is the best practice for aggregating values (e.g., sum, count, or average) from child records in a master-detail relationship. This feature automatically calculates the sum of all Order Line item totals and displays it on the parent Order record.

* The Data Import Wizard allows importing data while adhering to Salesforce's sharing and security model. By setting field-level security, sensitive fields can be hidden from unauthorized users.
* Other Options:
* Option A: Encrypting data externally is unnecessary since Salesforce has built-in security features.
* Option B: Using the Data Loader with Apex adds unnecessary complexity.
* Option D: The Salesforce CLI does not provide direct data import capabilities with security settings.

* Execution Flow:
* The loop runs 500 times (i ranges from 0 to 499).
* In each iteration, a new Account record is created and inserted.
* Governor Limits:
* This code violates the governor limit of 150 DML statements per transaction because each insert is executed individually.
* However, the code logically attempts to insert 500 accounts.
* Key Consideration:
* The code demonstrates inefficient handling of DML operations and would fail in a real-world scenario.
* Governor Limits: https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode
/apex_gov_limits.htm
References:

To query related child records in a lookup or master-detail relationship:
* Use the parent object (Gym__c) to retrieve its child records (Trainer__c) through a nested query.
* The child relationship name (Trainers__r) is derived from the lookup field.

* Visual Studio Code (VS Code) is the recommended tool for Salesforce development. It supports the Salesforce Extensions Pack for debugging and fixing issues in Lightning Web Components (LWCs).
* Not Suitable:
* Option A: The Developer Console is less effective for LWC debugging.
* Option B: The Force.com IDE is deprecated.
* Option C: Execute Anonymous does not provide tools to debug or fix LWC bugs.