Answer: D, Hope this helps!
Answer:
A social letter of introduction is a short letter written by a friend to someone well known to your friend in a place you plan to visit [B]
Explanation:
A social letter is a letter written in an occasion of a special event example of social letters are congratulatory letter, condolence letter as well as other special occasion letters like invitational letter. therefore in social letter of introduction it introduces you to a friend of your friend informing him or her of your visit
