Meaning of the idiom 'completely foxed"

English as a Second Language English Teacher Explanations (ESL Tests)
1

I really don’t know how to explain it as I am completely foxed.
a) absolutely sure
b) absolutely convinced
c) absolutely confused
d) absolutely curious

2

absolutely confused.

3

Hello Bev,

Did you infer the meaning from the context, or is this meaning in common use?
Because I looked it up, and the dictionary says that it means “Discolored with yellowish-brown stains”. No other meaning is listed there…
thefreedictionary.com/foxed

Thanks!

4

The meaning is in common use (In fact, more common than that of foxed paper or books!)
Look at definition 1 here:
oxfordadvancedlearnersdictio … nary/foxed