Explanation
Granular locking is an advanced tool that Salesforce can enable for large-scale role hierarchy realignments.
Granular locking allows finer-grained locking for certain operations that affect large data sets, such as bulk loading or updating. Granular locking can reduce the locking time and avoid performance issues when changing role hierarchy or ownership. Therefore, the answer C is correct and the other options are incorrect

Explanation
The three options that can change the owner of the opportunity are B, C, and E. The current opportunity owner can transfer the ownership to another user by editing the record or using the change owner button. The system administrator or a user with the "Transfer Records" permission can also change the owner of any record, regardless of the sharing settings. Someone above the opportunity owner in the role hierarchy can also change the owner, as they have full access to the records owned by users below them in the hierarchy. The other options are either incorrect or not possible.

Explanation
A new AccountShare record is created with Row Cause as "Manual" and Access Level as "Read/Write" when Paul manually shares the record with John. This record grants John edit access to the account owned by Paul.
Option B is incorrect, since an existing AccountShare record is not updated, but a new one is created. Option C is incorrect, since the Row Cause is not "Owner", but "Manual". Option D is incorrect, since an existing AccountShare record is not updated, but a new one is created.

Explanation
To make the sensitive fields accessible to the Human Resource team, other than field level security, another option is to create a new custom object with private OWD and Lookup relationship to Employee to store new restricted information. This will allow creating a separate security model for the new custom object, which can be shared with the Human Resource team using sharing rules or permission sets. Creating a new custom object controlled by parent and a Master-Detail relationship to Employee will not work, as it will inherit the same OWD as Employee, which is Public Read Only. Changing OWD of Employee custom object to private and a Lookup self-relationship to store only new restricted information will not work, as it will make all employee records inaccessible to other users who need them.