Answer:
A. Call for action.
Explanation:
An effective routine request is crucial as the way the author conveys his/her request would decide its worth and chances of acceptance for the readers. Thus, there are certain elements that assist in its cogency, beginning with a request containing significant time frames. Then, comes the call for action as it would elaborate and illustrate the basic idea and the action plan to the readers. This step is followed by the expression of acknowledgment or goodwill. Since the appreciation element is not among the given options, the best suitable and typical element would be the call or signal for the action.
