How to delegate administrative task in Active Directory?
If you want to delegate different administrative task to other administrator, you can use the Active Directory Delegation Tool to do this. Read below (copy from another board).
Active Directory Delegation of Administration
The Active Directory Users and Computers management console includes a Delegation of Control Wizard and has been around since Windows 2000. The delegation wizard assists you in granting an ordinary user (without super powers) to perform administrative tasks such as resetting passwords or managing security group membership. So rather than adding a user to the Domain Admins group, you can grant users the bare minimum security privilege they need to accomplish a specific administrative task.
Delegating administration is quite simple, open Active Directory Users and Computers, right click on an OU and select Delegate Control. A great TechNet article to follow is a Step-by-Step Guide to Using the Delegation of Control Wizard.