When developing a strategic HR plan, why is it critical for decision makers to clarify and write down assumptions about the external environment and the organization?

a$.$ to identify how staffing needs will change in both the short$-$ and long$-$term

b$.$ to identify inaccurate assumptions that caused expectations to fail to materialize

c$.$ to identify the changes that will have to be made to work systems to achieve the HR plan

d to identify who will lead future endeavors to achieve strategic HR plans