Imagine a guest speaker is to give a lecture and you're the one to make the speech of introduction. Which of the following goes first?

Imagine a guest speaker is to give a lecture and you're the one to make the speech of introduction. Which of the following goes first?
A.Welcoming the audience
B.Welcoming guest speaker
C.Introducing yourself
D.Introducing guest speaker
正确答案：Welcoming the audience