ambiguity with "you"

The lesson was covering "nous, vous, elles, eux" - all stress pronouns in the plural, and this is explicitly noted in the introductory comments on the lesson. There is no situation in the plural where 'toi' is correct - it is singular only. 

Remember 'vous' is the default in French for you in either singular or plural, and 'tu' occurs in 'permitted' use contexts only (essentially - it is by explicit or implicit agreement of the recipient of the address, not solely at the determination of the speaker).

Hi Chris,

Which example?

"vous" is used as second person (polite) singular and second person plural.

Without sight of the "example" you mention, difficult to help any further.

Jim

Chris is correct.

I got to this question from testing my knowledge of my study plan, not directly from the lesson (as suggested by Maarten).  So, for this question:

Nous? -- Non, pas _____________!   (Us? -- No, not you!)

Two of the provided answer choices would be correct (toi and vous):

toi, vous, eux, nous

This is a confusing question.  Or am I misunderstanding something?

Vous is correct every time. 

'Toi' only becomes 'correct' if the assumption is that the 2nd speaker restricts their response to the question about 'us' to only one of the people included in 'us', and speaks informally to them. 

Maybe it could be accepted as nearly correct, but it is not the 'best' answer.