Final answer:
The most courteous telephone conversation example is d. 'May I ask who is calling?' as it shows respect and politeness. This reflects good telephone etiquette, which is an essential part of effective communication and soft skills in both business and social settings.
Step-by-step explanation:
Among the options provided, the one that BEST demonstrates courteous telephone conversation is 'd. May I ask who is calling?'. Demonstrating telephone etiquette is significant in establishing a polite and professional interaction. It's part of broader social manners that govern how we interact with others in various situations, similar to knowing when to place a napkin on your lap at a dining table or how long to wait on hold during a call.
Using a polite greeting and asking for the caller's identity in a respectful way ensures clear communication and shows the caller that they are being taken seriously. It respects the norms of social decorum that are often taught as part of soft skills in a business or social context. On the other hand, answers 'a', 'b', and 'c' can be considered abrupt, disinterested, or commanding, which are not characteristics of polite conversation.