Controllable costs are best described as:

Controllable costs are indeed best defined as costs that can be managed or adjusted. This means that these expenses are within the influence and decision-making capacity of a manager or consultant. By making strategic choices and implementing various management practices, a consultant can affect these costs, optimizing them to meet organizational goals or budgetary constraints.

For instance, controllable costs may include expenses related to operations, such as employee wages, materials, and marketing costs. By analyzing and adjusting these expenses, businesses can drive efficiency and cost-effectiveness.

In contrast, expenses that cannot be influenced by the consultant refer to fixed costs that typically do not change with the level of activity, so they are not within the control of a manager. Fixed costs, unlike controllable costs, remain constant regardless of business performance. Future expenses requiring high investment could encompass a broad range of financial considerations, not limited to controllable factors, and may involve strategic planning rather than immediate adjustments.