Final answer:
The functional matrix is the least similar to the pure project organizational form.
Step-by-step explanation:
The functional matrix is the least similar to the pure project organizational form. In a functional matrix, the project manager has limited authority and operates within the existing hierarchical structure of the organization. This means that the project manager does not have full control over resources and decision-making, which is a key characteristic of the pure project organizational form.
On the other hand, in a strong matrix, the project manager has more authority and control, resembling the pure project organizational form to a greater extent. A balanced matrix also provides a more balanced distribution of power between the project manager and the functional heads.
Therefore, the correct answer to the question is d) Functional matrix.