Your organization has two business units: Sales and Operations. The sales unit includes three units: East, West, and Central. The Operations unit has two units: Accounting and Engineering. The Sales unit manager has Read Account privilege access set to Parent: Child Business Units level. The manager in the Accounting unit has Read Account privilege access set to the Organization level. And an engineering manager in the Operations unit has Read Account privilege access set to the Business unit level. 
Please select all correct statements about security role privileges for each of the managers.

Answer options:

A.The engineering manager can view all accounts owned by the users in the Sales unit
B.The accounting manager can view all accounts owned by the users in the West unit
C.The engineering manager can view all accounts owned by the users in the Engineering unit
D.The sales manager can view all accounts owned by the users in the Sales unit and sub-units
E.The accounting manager can view all accounts owned by the users in the Engineering unit

Correct Answers: B, D and E 
The Business unit security model is the basis for the Dataverse security. The model controls access to the data using security roles, teams, and users. By linking all of them together, you are getting a role-based security model. By default, the Organization is a top-level of a business unit hierarchy. Each business unit has a default team. You cannot change or delete the default team. You must assign every user to only one business unit. 
The business unit security model uses security roles to assign them to the users or teams. A team also can consist of users from different business units. Option B is correct because the accounting manager has the Organization privilege access level. This role can view all accounts in all business units of the organization.
Option D is correct because the sales manager in the Sales unit has the Parent: Child Business Units privilege access level. This role can view all accounts in the Sales unit and all child, grandchild, etc. business units of the Sales unit.
Option E is correct because the accounting manager has the Organization privilege access level. This role can view all accounts in all business units of the organization.
Option A is incorrect because the engineering manager belongs to the Operations unit with the Business unit level privilege access. This security role can view all accounts owned by the Operations unit users only with no depth of child or grandchild units. The engineering manager cannot view the accounts owned by the users in the Sales unit.
Option C is incorrect because the engineering manager belongs to the Operations unit with the Business unit level privilege access. This security role can view all accounts owned by the Operations unit users only with no depth of child or grandchild units. The engineering manager cannot view the accounts owned by the users in the Engineering unit.
For more information about Dataverse business units security, please visit the below URLs: 

https://docs.microsoft.com/en-us/power-platform/admin/security-roles-privileges
https://docs.microsoft.com/en-us/power-platform/admin/wp-security-cds
https://docs.microsoft.com/en-us/power-platform/admin/create-edit-business-units
https://www.youtube.com/watch?v=8UWSj-vvxzU