You can guess the answer working on the options. The effective work in work-related information means direct work. D is not correct. It can be easily seen that if the concern cannot be solved by your colleagues when it is questionable and not probable. The choice B is also not correct. Letters and phone calls take time. If the work has to be monitored to the manager when the manager's function involved, the choice C is not correct. In this case, the work is going to be indirect. However, in option A the work can be viewed as effective since you report your work to the manager who knows what to deal with.