A、Hospital staff only. B、Many Packer Hall residents. C、Many officials. D、The art students. C本题问“谁会参加步行马拉松?”男士说“你不知道吗，Packer Hall

W: Hey, Joe, what is all this talk about the benefit walkathon this weekend?
M: Don’t you know, most of the residents in Packer Hall are going to try to walk the seven miles from the engineering library, across campus and down to city hall, in an effort to raise money for the new children’s hospital.
W: Sounds like a good idea. But I don’t understand where the money comes from.
M: Well, a few days before the walkathon, each participant goes around asking people to pledge just a certain amount of money for each mile that he or she expects to walk in the event. Then after the walkathon’s over, the participants go back to those same people, collect the money pledged and send it into the hospital.
W: So you mean if someone pledges, say, a dollar a mile, and you walk five miles, you get five dollars?
M: That’s right. Of course, most of my friends aren’t such big spenders, the biggest pledge I’ve gotten so far is 25 cents a mile.
W: And how many people have made pledges for you?
M: Eleven so far. Say, how about making it an even dozen?
W: Sure, if you do the same for me. The walkathon sounds like a perfect opportunity for me to break in my new pair of sport shoes.
M: You are definitely warm-hearted.
W: You bet. And I ten you, I am also a good walker.
M: Hope to see you in the walkathon.
W: I will be there.
Who are going to be in the walkathon?