Which one/which ones

[TeacherMarco]

The text below is just an example:

Enterviewer: Do you take drugs?
Enterviewee: Yes.
Enterviewer: Which one / which ones?
Enterviewee : pot.

The point is : Which one should I use in the text above? Which one or which ones?




Thanks a lot.

Marco.

[Mike2010]

The text below is just an example:

Enterviewer: Do you take drugs?
Enterviewee: Yes.
Enterviewer: Which one / which ones?
Enterviewee : pot.

The point is : Which one should I use in the text above? Which one or which ones?




Thanks a lot.

Marco.

As the interviewee has simply answered 'yes' to this question, which uses the plural ('drugs'), continuing with 'which ones?' seems fine.