The correct answer is A. A courtesy
Step-by-step explanation:
In communication, attentiveness refers to showing attention to others especially in terms of showing you listen and are interested in other's ideas, opinions, proposal, etc. Due to this, attentiveness is one of the elements that are necessary for effective communication allowing you to become an effective listener and therefore answer or interact appropriately. Besides this, attentiveness is considered as a courtesy or a respectful act with other people. Considering this, it can be concluded attentiveness is a courtesy.