A、  B、  C、  A询问动作主体(lead the seminar)的who疑问句→回答人名

When will the plant start manufacturing?
(A) In less than 3 months.
(B) The plants are tall and green.
(C) It is located in Mexico.

Who will lead the seminar this time?
(A) Doctor Sara, I suppose.
(B) I’ ve already signed up for it.
(C) Mr. Song retired last year.