Correct Answer: ACTo ensure that fields with field-level security permission of read-only on certain users’ profiles are not being updated by the custom Apex class, the correct approach is to use the isUpdateable() Apex method. This method checks if a user has edit/update access to a field, allowing the code to conditionally perform updates only when the user has the necessary permissions. Other methods like WITH SECURITY_ENFORCED in SOQL statements enforce read access but do not verify edit access, and the With Sharing keywords deal with record-level access instead of field-level security.