单选题：根据以下材料，回答题Although the notion of human resource planning is

根据以下材料，回答题
Although the notion of human resource planning is well established in the HRM vo-cabulary, it does not seem to be commonly practiced as a key HR activity. As Rothwell(1995) suggests,"apart from isolated examples, there has been little research evidence of increased use or of its success". She explains the gap between theory and practice as ari-sing from:
(1) The impact of change and the difficulty of predicting the future-- "the need for planning may be in inverse proportion to its feasibility";
(2) The "shifting kaleidoscope" of policy priorities and strategies within organiza-tions;
(3) The distrust displayed by many managers of theory or planning--they often pre- fer pragmatic adaptation to conceptualization;
(4) The lack of evidence that human resource planning works.
Be that as it may, it is difficult to reject out of hand the belief that some attempt should be made broadly to forecast future human resource requirements as a basis for plan-ning and action. On the basis of research conducted by the Institute for Employment Stud-ies, Reilly (1999) has suggested a number of reasons why organizations choose to engage in some forms of human resource planning. These fall into the following three groups.
(1) Planning for substantive reasons, that is, to have a practical effect by optimizing the use of resources and /or making them more flexible, acquiring and nurturing skills that take time to develop, identifying potential problems and minimizing the chances of making a bad decision.
(2) Planning because of the process benefits, which involves understanding the pres-ent in order to confront the future, challenging assumptions and liberating thinking, mak-ing explicit decisions which can later be challenged, standing back and providing an over-view, and ensuring that long-term thinking is not driven out by short-term focus.
(3) Planning for organizational reasons, which involves communicating plans so as to obtain support/adherence to them, linking HR plans to business plans so as to influence them, regaining corporate control over operating units, and coordinating and integrating organizational decision-making and actions.
According Rothwell (1995), the gap between human resource planning theory and practice arised from the following except__________. A．the impact of change and the difficulty of predicting the future
B．the dramatic change of policy priorities and strategies within organizations
C．the distrust displayed by many managers of theory or planning
D．the redundance of evidence that human resource planning works