What department is the new girl in vs. Which department is the new girl in?

[Tedcruise]

English Language Tests, Intermediate level

ESL/EFL Test #146 "Conversations and Comprehension Test", question 6

Anne: Do you know the new girl in the mailroom?
Richard: No, but I think she's Cathy's friend.
Anne: We should ask Cathy to introduce us at lunch.
Question: What department is the new girl in? ..........

(a) Cathy's department
(b) The reception area
(c) The mailroom

English Language Tests, Intermediate level

ESL/EFL Test #146 "Conversations and Comprehension Test", answer 6

Anne: Do you know the new girl in the mailroom?
Richard: No, but I think she's Cathy's friend.
Anne: We should ask Cathy to introduce us at lunch.
Question: What department is the new girl in? The mailroom.

Correct answer: (c) The mailroom
_________________________

I think there are some problems about this questions : What department is the new girl in ?
I am not sure but it should be : which department
is the new girl in ?
Right ??? I am becoming confused , LOL.

[Alan]

HI,

There is a slight difference. 'Which' is more precise but 'what' in this sentence is all right.

Alan
_________________
English as a Second Language
You can read my ESL story Present Simple