The unique identifiers assigned to each item of a WBS are often known collectively as:

C

Code of accounts, so answer C

The answer is :

C. The code of accounts

C. The code of accounts

Based what I have found my answer is A. The work package codes

Each item in the WBS is generally assigned a unique identifier; these identifiers can provide a structure for a hierarchical summation of costs and resources. The items at the lowest level of the WBS may be referred to as work packages, especially in organizations that follow earned value management practices. These work packages may in turn be further decomposed in a sub-project work breakdown structure. Names for work breakdown structure levels: 

1. Program
2. Project
3. Task
4. Subtask
5. Work Package
6. Level of Effort

C I think

It should be the code of accounts (C)

My answer is choice (C) The code of accounts

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I think it is A

Code of Accounts. - this is a project management tool which assigns a code made from numbers, letters or a combination of the two to every item on the WBS of a project.

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