Answer
Directory Services
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<u>Definition</u>
It is a type of software that is used to unify and customize the resources available at the network.
<u>Explanation</u>
This software is used to gather the information and addresses of all computers connected on the network.
It is a type of information store, where all the information related to resources (computer) and services of network has been stored. It also gives administrator rights to the single point to manage whole network resources.
This is the reason, Option "D" is the best choice for me as sole IT employ in a company. I will prefer directory services software to gather the information of all computers of organization and manage users in company.
A. He has not saved the document yet.
reason being is that most documents today will change their title on what it is thats written on the paper unless you personally change it yourself