Final answer:
Bob excels at the planning and organizing management function. Hence the correct option is A.
Step-by-step explanation:
Bob's ability to determine what needs to be done and by whom aligns with the functions of planning and organizing. Planning involves setting objectives and determining the actions needed to achieve them while organizing involves arranging resources and tasks to implement the plan effectively. In this case, Bob is demonstrating proficiency in identifying tasks (planning) and organizing them by assigning responsibilities to individuals. The other options (Staffing and leading, Leading and controlling, Planning and controlling) involve different aspects of the management process, but planning and organizing best capture the described scenario. Hence the correct option is A.