To help the top-level management co-ordinate the activities is the function of the middle level management.
Explanation:
The function of the middle-level management is to help the top-level in co-coordinating the activities. Plans and policies are framed by the top-level managers but they have no use until they are properly communicated to the lower levels of management. This work is done properly by the middle-level management.
The correct option is A.